Actually, if you can measure it arcuately enough, the bowling ball will always hit the ground first because it is less affected by atmospheric drag (compared to the force exerted on it by gravity) no matter what height you drop the balls from. The difference will be miniscule from a height of a few meters though.
Thank you ... its sad that people both (a) don't understand that gravity works the same regardless of weight and (b) on any planet with an atmosphere, atmospheric drag should be considered.
Let's take out air completely, if we can measure as accurate at the levels billionth of the width of a proton we will see that the heavier object "hits" the ground first, because a heavier object has its own gravity too which attracts the earth towards it. But of course the difference has no practical meaning.
The question stems from the elimination of the outside factors of such as drag. We know which one hits the ground first. Thats why you can't survive falling from a building but a squirrel can. 1 the squirrel isn't heavy enough to produce a velocity big enough to kill it and 2. The drag on it due to it being so light negates the fall. The question still remains true though, they both fall at the same initial velocity, regardless of any factor. TERMINAL velocity, however, is a different story. But, if both objects fall before reaching terminal, they hit at the same time. That's not up for negotiation.
When analyzing the forces on a moving ball, if we assume both balls are at the same speed, we can see that for a light ball, the air resistance is large relative to its gravitational force, while for a heavy ball the drag is small compared to the gravitational force. Because of this, drag has a much larger effect on a lighter object, and a heavier object will always accelerate faster and reach higher speeds than a light ball when falling through a fluid.
Thought before the video: It depends on the hight you drop it from. There are to major forces that work here. One is the gravitation and the other is the air resistance. The gravitational force is constant and dependend of the weight of the droped object. The other gets greater the faster the object falls. At the start both balls accelerate with normal falling acceleration of ~9.81 meter/second². The faster the balls falls the greater is the influence of air resistance and the acceleration slows down. The heavier ball will allways be faster if droped in the atmosphere but the difference gets unrecognisable at low hights.
You're right I was showing students this experiment by filling balls of the same size with sand and one ball was heavier than other and when dropped from the first floor of the school building both touched the ground at the same time, when one of the teachers made video in slow motion results were not same.
hey I must say it is a pleasure to stumble on a channel that goes in details about questions that are commonly brushed away with a simple but inexact "well known" answer, I am a mechanical engineer and I'm more and more concerned about the false assomptions that are becoming common in the field so thank you for your great work in explaining these phenomenas !!
You can always go into further detail, like the fact that the stated G will be different than real because noone accounted for Gravity weakening with one over the square of distance. G=M1*M2/R^2. Where R0 is the radius of earth, and object dropped.
@@ГеоргиГеоргиев-с3г yes. And the fact that the drag is depending on the velocity is not explicitly said here too. In general it was taken into account here but when he explained the reason for the difference between the steel ball and that heavy blue ball he explained it with a constant force. In fact the drag increases with the velocity. So it is not constant and as the balls get closer to their terminal velocity the difference in the acceleration increases. It is basically a continuous process. All the different forces that contribute to the movement are not really constant but change depending on different factors. The gravity is depending on the mass, which is constant for each ball, and the distance to the ground. However, the distance to the ground doesn't cause a big difference if they are dropped from the same height. It only changes the predicted time until the ball hits the ground. The fact that the drag is depending on the velocity and that this change is much more rapid than the change in gravity is basically the reason why there is a terminal velocity at all. The density of the air is also a factor as he already said at the end of the video.
Agree. There is more and more stupid in this world and unfortunately much of that is thanks to a bad academic system. Having said that, this educational video is also built up in a to complicated way and is repetitive. Treating people like they're stupid results in stupid people.
Okay I'm at 3:32. So inertia, if i understand correctly, heavier denser objects have more resistance to change in motion because there are a lot more atoms inside their composition. And probably every single atom has its own resistance to a change in motion. And so them more atoms equals more resistance to change in motion because every atom has its own resistance to that change in motion which adds up when put together.
If you slow it down you can see the bowling ball start slightly above the basketball and the bowling ball hits the ground slightly before the basketball. And this is before terminal velocity takes affect.
I enjoyed this, thanks. Since you already included a brief shot of skydivers, you could also have mentioned that an object that can change the amount of surface area it presents to the air resisting it can influence its freefall velocity. This is exactly what skydivers do in order to catch up to those who have exited the plane before them, and also (more subtly) to stay "on level" with the people they are jumping with.
One other way to think about it is that the speed of the ball is impacted by two forces - 1) The downward force of gravity 2) The upward (backward) force required to push the air out of the way. These forces cause an acceleration by Newton's Law rewritten as a=F/M. Since the force due to gravity is Fg-Mg them the acceleration caused by gravity is the same for all objects a=Fg/M=Mg/M=g. This is not true for the acceleration caused by the air. That force is not affected by the mass of an object but only its speed and air resistance so since a=F/M, if you increase the mass of the object then the acceleration will decrease and since that acceleration is upward (backward) the object will fall faster. The velocity when this value is the same as the acceleration due to (g) is the terminal velocity since at that point the two accelerations cancel each other out and the object will stop accelerating (its velocity will stop changing).
That ball would not drop. The Earth would drop to the ball ;-). The basketball would not fall to earth but to the superheavy ball. Earth as we know it and the basketball would be obliterated.
This is THE explanation of non lab fall physics I needed for at least 10ys, concise, easy to understand, well animated, with some IRL footage ontop - thank you. well, need is an overstatement, and the reason for it is banal, but still, things that knaw at you in the back of your mind after an argument in reallife and/or online. One of these was about a story where a character could change their weight and through that, among other use cases, fall faster, and a lot(!) of people came along with lab-condition rules to claim its lack of realism, totally ignoring air resistance, terminal velocity etc (not that I could explain that well enough, but the argument always was 'that's negligable' .... now I will lead them here :D )
I would be curious as to what you mean by the character would be able to fall faster. I know if someone told me about a character that could change their weight and was able to fall faster by increasing their weight I would give the same response that the character wouldn't actually fall faster. However that is because the wording makes it sound like if they increased their weight their acceleration would go beyond 9.81m/s^2 which would be mostly incorrect (Unless the character could increase their mass so much that the acceleration due to gravity increased by a noticeable amount). However if you were explaining it more as the character could increase their mass to reduce the effect of air resistance during their fall making their acceleration stay closer to 9.81m/s^2 for longer then I would agree but again that would only be really noticeable in very long falls and most of the time how the character positions themselves during the fall is going to be the main factor in their air resistance.
If dropped one at a time so that they can't effect each other the heavier object will hit in less time. The only reason it's not apparent with bowling balls is their negligible mass compared to the Earth. For example if it were a case of dropping a bowling ball and a neutron star then the latter would hit first because the Earth would rapidly fall towards it too.
Interesting point, but any situation extreme enough for that to be significant would likely deform the shape of the planet prior to the drop, which I think would actually lower the surface gravity of the planet. Though I’d have to think about this some more.
@@LeTtRrZ I suppose that my point is that although the bowling ball's attraction of the Earth is so small that it's probably less than the width of a proton it's still there, the Earth would still move and by more than with the feather. The reason I suggested dropping each individually is that otherwise it's much like taping the objects together, Earth is being pulled in the same direction by the combined mass of both if dropped together. There's also the point that rather than the objects falling towards the Earth, they and the Earth both fall towards their barycentre, which given the difference in sizes is somewhere very near to the Earth's centre of gravity. It depends on how picky you want to be but tiny effects are still real even if barely significant
Me: I hope this helps... According to the laws of physics, heavy and light objects fall at the same rate when air resistance is negligible, meaning a heavier object does not fall faster than a lighter one; they both experience the same acceleration due to gravity. Explanation: Gravity pulls on all objects equally: The force of gravity acting on an object is directly proportional to its mass, but the acceleration due to gravity is constant for all objects near the Earth's surface, regardless of their mass. Air resistance can affect the perception: In real-world scenarios, air resistance can make it seem like heavier objects fall faster because lighter objects with a larger surface area experience more air resistance, slowing them down more significantly. Key point: If you were to drop a bowling ball and a feather in a vacuum chamber, where there is no air resistance, they would hit the ground at the same time.
At the same time. A simple thought experiment demonstrates this. Imagine a light object tethered to a heavy one. If they fell at different speeds would the lighter one cause the heavier one to fall more slowly or would it cause the lighter one to fall faster? Hence a contradiction. So they must fall at the same speed.
Shoutout for the conserve ¥ you go to evenpoint, RELEASE the two > 1 falls, the other int even. For mass stays SAME, when releasing some a is byproduct. Descending is in a way faster, for it ultimates in an impact, than orbiting. FASTNESS give by Fg < a,N
In the first situation,(empire state building hight fall, in regular atmosphere) the bowling ball will hit ground first - It's high enough that atmospheric drag would come into play, and I daresay that the basket ball would reach terminal velocity. However, in a vacuum they'll hit the floor at the same time.
Lol, you’re the only one to have mentioned it but it bothered the hell out of me in the edit! Bad planning between the wide and close up shots, budget didn’t stretch to 2 slow mo camera 🤷♂️ Thanks for watching and commenting though 👍
Could you make a video about which weighs more, a pound of feathers or a pound of bricks. Because I feel like if you gather a pound of feathers, the air in between the feathers will add to the weight. But not sure if that can be debunked. Or maybe if its 100 pounds of bricks VS 100 pounds of feathers, might it then have a difference?
@@DebunkedOfficial Or instead of feathers switch to cotton. It's probably easier to see if the air makes a difference on regular cotton vs compressed cotton
@@arothmanmusic equal, because length measurements are still. Meanwhile weight & velocity measurements can be affected by air, pressure, and a few other elements like shown in this video
David Scott did this very experiment on the Moon in 1971, on Apollo15. using a falcon feather and a rock hammer, and they landed at the same time. The moon has no atmosphere. There for is a perfect vacuum environment. 😊
So what might be the fastest an object move due to gravity after being dropped? For example a one ton lead filled aerodynamically stable arrow or dart dropped from the space station.
This is actually something under development as a weapon. I think it's called "arrow from god" or "project thor", something like that. Don't remember what speed they would reach, but it's stupidly fast, and has a massive amount of kinetic energy.
😆 I don’t actually remember why, but my animated character has always had a white t-shirt on, so I thought I should go with continuity and match as we were bringing the experiment to life. I hope it didn’t ruin it for you? Thanks for watching and commenting! 👍
that's cuz it's rubber (elastic) and hollow on the inside so when it hits the ground Newtons 3rd law acts on it (the ground pushes back with the same force) hence it deforms the ball a little and compresses the air inside which immediately pushes back against the bottom and the ball bounces off
@@kami3595 . Ah I see. Then the other ball being not hollow but full and composed of a strong heavy material made it more resistant to the deforming caused by the equal opposite force to it's impact on ground. Plus no air inside it to be compressed like the bouncy one.
1:31 You can clearly see the bowling ball being behind the basket ball but it catches up because of less drag 9:53 The acceleration is not constant as the drag increases as the velocity increases. Purely mathematically the ball will never reach the terminal velocity but just approaches it. Of course in practice there are variations like wind that mess things.
Yep, I hardly ever see this particular point raised. Purely mathematically, terminal velocity is an asymptote. However, like you said, in reality things aren't quite so clear cut, perturbations, cross-winds, hot and cold patches in the air, etc.
From 1:31 you can see the bowling ball is slightly higher when released. Yet the frame on 1:34 shows the bowling ball hit at the same time. This means the heavier ball was traveling faster not at the same speed. Yes this is due to air resistance but that was not mentioned at the time.
Extremely nerdy footnote: Even in vacuum the ball with a larger mass will hit the ground first by an extremely small amount without violating Newtonian mechanics. When a mass falls you have to realise that the Earth is also gravitationally attracted to it. The force of the ball on the Earth is the same force of the Earth on the ball (Newton's third law) but the ball accelerates way more due again to the fact that it has very little inertia compared to the planet. That said, the ball and the Earth will both move towards their barycenter (which is extremely close to the Earth's center of mass due to the fact that it has many orders of magnitude more mass than the ball). This means that the ground would move towards the ball by an extremely small amount. If the ball has a larger mass, the ground will move upwards quicker. Still by a crazy small amount. If you perform the same experiment in the vacuum twice (just changing the mass of the dropped object) you will see that the more massive one will arrive first 😂
But if you drop the two balls side by side simultaneously, as per the examples, then would there still be a difference? The pull of the heavier ball on the earth would also draw the earth towards the lighter ball.
@@koalamusik yes. But this effect is even smaller than the gravitational acceleration of the earth towards the ball. If there is one airplane flying on the other side of the earth this will already cause a completely different outcome of the experiment according to that. Those effects are so small that you can't measure them. They are only causing a significant difference if the mass of the objects is in a comparable order of magnitude.
@@simsch97 even small effects/forces don't disappear if you want to be 100% precise. And in this theoretical experiment we were talking about a closed system with only one earth and two balls
Going back to the penny drop... What if the balls were the size of the penny (albeit spherical)? The mass is greatly reduced and therefore the air resistance. With that in mind, I would like to think the terminal velocity would be achieved much faster for even the heaviest.
The best science channel on youtube, Veritasium, made a video called "How dangerous is a penny dropped from a scyscraper?" which you might find interesting.
I absolutely love gravity. From learning how it is created to Newton and then Einstein. I encourage all to go down the rabbit hole and really learn the fundamentals of Gravity. You won't be disappointed.
Precisely what I'm doing, I would've never came here and searched this if I wasn't studying physics. My understanding completely changed 30 minutes ago when my notes simplified said a=g so I came here lol
08:25f The 2 heavier balls won't accelerate at the same rate but the heavier ball will accelerate at a higher rate long before the middle ball reaches its terminal velocity.
I tried to tell my teacher not to wake me while I'm sleeping in class because "I'm an object at rest and objects at rest tend to stay at rest" but it didn't work 😂
In a much longer drop, say from 2000 feet, the basketball will hit it's V max much sooner than the bowling ball due to air resistance. From a short drop the difference might be in fractions of milliseconds and would depend on very precise release.
Technically the heavier one is also pulling on the earth by an infinitesimally stronger amount than the lighter one, making it *technically* faster by a tiny, tiny, tiny, amount. But for the sake of simplicity, yes,it is the same.
Explanation at the end of this video may cause confusion, I hope this helps; The air resistans isn't like say 3 Newton, until you reach terminal velocity and you stop accelerating. It will grow along with the square of your speed, therefore it can be easly shown that a lighter object of the same aerodynamic properties will always stay behind, it is hard to calculate the exact differences without a calculator at hand.
Go back and watch the house drop, they don't hit the ground at the same time for the same reason you describe at the 9 minute mark. They are just so close together you think they hit at the same time.
They both accelerate at the same rate but one got a higher terminal velocity. Also air resistance is a thing and will affect more the lighter/larger object. Didn't watch, tell me i'm right.
Increase the size of the balls until one is the size of Jupiter and the other is the size of Earth. Release them separately and measure the time of takes. The Jupiter ball will hit the The ground faster. It attracted Earth in it's direction. Using a single frame of reference, it fell faster
5:32 since the two forces pushing up and pulling down are equal at terminal velocity, imagine a world where you would just float in the air, unable to move until acted upon by another force.
It all depends on the level of accuracy you are aiming for. If you could measure at ridiculous level of billionth of the width of a proton you will see that the balls too has its own gravity, thus they also attract Earth, and heavier object will attract the Earth more.. so even if we remove atmosphere, in reality it is always the heavier object that hits the ground first, but the measurement accuracy is so small it is not even practical.
Thank you so much! Every time I see/here people replicate the thought experiment with vacuum I get the impression that nobody has _actually_ thought through the test setup and result. They all treat the ground as a fixed reference frame and use objects with pretty similar masses. But what if one of the test objects is, say, the moon? The point of this experiment as I understand it is to show that it is not the objects _own_ mass that _causes_ it to fall. But the time till it hits the ground should still depend on _both_ involved objects because the really fall towards each other. I am NOT a physicist, maybe I am missing something.
In the vacuum, objects fall at the same speed. True, the heavier object pull is greater, but so is its inertia, which makes it harder to move. And it turns out that these two effects cancel each other out.
Commenting before watching ... I think they'd hit the ground at the same time if dropped in a vacuum... but with wind resistance affecting a basketball more than a bowling ball, over a high drop, the basketball may skew more to the side and take longer to drop.
Fun Fact, The feather and bowling ball was actually recreated on the moon during Apollo 15. Except he swapped out the bowling ball for a rock hammer. This was performed by Commander David Scott, not only that, it was broadcasted live on TV. It indeed demonstrated that both items, within the vacuum of space, fell at exactly the same rate and landed at the same time. Pretty cool if you ask me 🙂
@DebunkedOfficial which part of the video exactly? Yes you included footage of 'an experiment' done by NASA, the one inside a vacuum chamber here on earth. I was referring to the one done on the moon during an EVA on Apollo 15 in 1971. It was done for publicity, mainly to get kids enthusiastic about science.
tl;dr yes, but to a point, everything will eventually hit terminal velocity if given enough height and time. though the object that achieves it faster will obviously be further down
In vacuum everything falls at the same speed. As simple as that. There was a little bit of a popular science demo when one of the Apollo astronauts on the moon dropped a hammer and (i think) a feather and they fell at the same speed..... and that's not because of 'the moon' but because of 'the vacuum'.
So gravity alone doesn’t intensify the gravitational force based on the weight and mass of an object but atmosphere AKA air does give resistance and has a greater effect on lighter objects because of a lesser weight and velocity on air molecules. I think somewhere in this experiment is the answer to why super massive black holes at the centre of galaxies propel stars around it evenly throughout when again our intuition would have us believe stars closest would be more affected and orbit faster.
Guess I'm just dumb but I'm not grasping how "inertia" of a heavy object means it's going to be harder to stop it's fall, combined with gravity accelerating that object's fall, results in any cancellation of forces ????
Question about finding the heavier object's terminal velocity: Why not instead of increasing the height, you just start with a greater initial velocity like -100m/s at t=0 instead of 0m/s at t = 0?
Question: Why snake venom is much stronger than it needed to kill it's prey instantly. How the snakes around different places of same species have difference in there venom compositions. Example Inland taipan
Also, if the object is small enough, bouyancy effects might come into the picture. For objects the size of a pea or at the very least a grain of sand, I don't think you will get the same result. I am glad rain drops don't fall at the speeds described in the video!
Basically the heavier balls have a higher speed cap and better gravity, but inertia compensates, but gravity increases and inertia does not, but the basic balls have neither of them. Also too, air resistance doesn't change.
They will hit the ground at _almost_ the same time. In the absence of atmosphere, they would land at _exactly_ the same time because gravity acts on all mass equally. However, due to atmospheric drag, the lighter of two equally sized objects (in this case, the basket ball) will hit the ground slightly after the heavier. The difference from atop the Empire State building between a basketball and a bowling ball would ultimately only be a fraction of a second. However, the difference would be significantly more noticeable if you were to compare an iron shotput and a whiffle ball of equal diameter, or if you were to drop the two balls from a more significant height.
In Vacuum: Give one of the test objects the mass of the moon and don't treat the earth as a fixed reference frame. Do both test objects hit the ground at _exactly_ the same time?
@@carstenbohme8813 Excellent. The ball with the mass of the moon will surely attract the earth, but the other basket ball will benefit of it too. But the moon ball will also attract the basket ball, and this will totally disrupt the "equality of fall time" And even further, with a ball of the size of the basket ball but with he mass of the moon, many relativistic effects are expected!!!
So, if each ball was dropped from the height needed to achieve their respective terminal velocity and were dropped at the exact same time, would they hit the ground at the same time?
the balls don't accelerate at a constant rate. as the velocity increases, the air resistance increases, so the ball's acceleration gradually decreases until it hits 0.
That’s why parachutes don’t work on the moon despite having low gravity. Air resistance can also generate heat if objects fall at a much greater height such as a meteor which falls to earth at the minute it enters our gravitational pull.
Additional (or instead): Do *denser* objects actually fall faster than light objects? *Sentence case* seems more suitable to "question titles" like this. You can't debunk a *question!*
ýes its true that the weight doesnt effect how fast something is dropping but the air resistance does. becausse the bowling ball is smaller it automaticly makes it the object that will hit the ground first if let go off at the exact same time, dropping it by hand from 2 meters high while cutting the final drop multiple times is the most unscientific way to show it
Leonardo da Vinci disproved this nearly 600 years ago at RISK of HIS LIFE for "heresy" against the Catholic "Church"! He dropped a small cannon ball and much larger and heavier cannon ball (NOT from the Tower of Pisa as the myth goes) from a height of about 400 feet and they hit the ground simultaneously. That's how he GREATLY improved the science of exterior ballistics (accuracy) of the cannons. My lab partner and I proved it in my Junior year of High School Physics I on the third floor of the Old Central High School in downtown Tulsa in 1969 with ball bearings dropped down the stair wells three floors. We also proved the Earth is round and calculated it's diameter to 1%, how long an "hour" is, that the Earth moves around the Sun, the size of a molecule, therefore an atom, and LOTS more!
Gravity is based on size and expansion not mass and attraction. Gravity is simple Galilean relative motion. The earth is approaching- expanding at 16 feet per second per second constant acceleration- the released object. “The Final Theory: Rethinking Our Scientific Legacy “, Mark McCutcheon for proper physics.
Why complicate that much? The one that will hit the ground first is the one with less air drag, doesn't matter the weight. Given the time and velocity necessary for it to get in action.
Very good but incomplete. let's says I add a fourth ball of a *mass* of 1g. I really means 1 gram of mass. A typical basket ball volume is 7 liter (yes, I checked twice, r=1.19 dm =>7 liter ). So filled with helium, 1 bar at 20°C , 0.1g / liter we have 0.7 gram, plus 0,3 gram of rubber => 1g. But the density of air 1bar / 20°C is 1.2 g /liter, so 7 liter of air is 7* 1,2 = 8,4g. So the 4th balloon got a Archimedian up force of 0.0084 * 9.81 N , and a gravitational force of 0.001 * 9.81 N-> *it goes up!* All of that to explain that archimedian force is here too. If we want to be perfectly exact, we need to be careful with the term *weight* . Because the real definition of the weigth is "on the location of experience, the *force exerced by the still object on the ground* ". And this is *not* exactly equivalent of "the force of gravity exerced by the planet on the object". For example, the weight at Quito is the result of 3 forces: - the gravitational attraction of the earth on the object - the centrifugal force created by the earth rotation (it is not so small, at the equator 0.03 m/s², nearly 0.3% of the gravity) - the Archimedian force So, in the air, 1kg of lead is heavier than 1kg of feather. Because the net volume of 1kg of feathers is bigger than the volume of the lead, so the archimedian force is bigger. To effectively measure that, you have either to measure the 2 masses in the vacuum, or to measure the mass by it's inertia, not by weigth. :D There is even one other factor in your experience. It is coriolis effect. It will not measurably change the time of fall, but it may measurably offset the location on the ground.
Actually, if you can measure it arcuately enough, the bowling ball will always hit the ground first because it is less affected by atmospheric drag (compared to the force exerted on it by gravity) no matter what height you drop the balls from. The difference will be miniscule from a height of a few meters though.
THIS!!
I knew it!
Thank you ... its sad that people both (a) don't understand that gravity works the same regardless of weight and (b) on any planet with an atmosphere, atmospheric drag should be considered.
Let's take out air completely, if we can measure as accurate at the levels billionth of the width of a proton we will see that the heavier object "hits" the ground first, because a heavier object has its own gravity too which attracts the earth towards it. But of course the difference has no practical meaning.
The question stems from the elimination of the outside factors of such as drag. We know which one hits the ground first. Thats why you can't survive falling from a building but a squirrel can. 1 the squirrel isn't heavy enough to produce a velocity big enough to kill it and 2. The drag on it due to it being so light negates the fall. The question still remains true though, they both fall at the same initial velocity, regardless of any factor. TERMINAL velocity, however, is a different story. But, if both objects fall before reaching terminal, they hit at the same time. That's not up for negotiation.
TL:DR Q: "Does gravity exist" A: "Yes."
B. Not No
C. Don't forget air resistance!
No we are running out of gravity.
D. It's all a simulation
D: sir Isaac Newton invented it
When analyzing the forces on a moving ball, if we assume both balls are at the same speed, we can see that for a light ball, the air resistance is large relative to its gravitational force, while for a heavy ball the drag is small compared to the gravitational force.
Because of this, drag has a much larger effect on a lighter object, and a heavier object will always accelerate faster and reach higher speeds than a light ball when falling through a fluid.
What objects do you have close to hand to test this out right now?
My balls
Working on Wind Turbines, I could chose from a variety of heavy tools to drop down - for science:P
@@Kezenmacher Sounds like a cool job!
I could drop a few cats from the top of my house. The question I have is, will they land on their feet?
@@diyeana aha sounds like a new Debunked in the making! Thanks Melissa 👍
1:30 heavier ball DID hit the ground first even despite being released a bit higher.
Yes.
Yes
Thought before the video: It depends on the hight you drop it from. There are to major forces that work here. One is the gravitation and the other is the air resistance. The gravitational force is constant and dependend of the weight of the droped object. The other gets greater the faster the object falls. At the start both balls accelerate with normal falling acceleration of ~9.81 meter/second². The faster the balls falls the greater is the influence of air resistance and the acceleration slows down. The heavier ball will allways be faster if droped in the atmosphere but the difference gets unrecognisable at low hights.
If dropped in a vacuum they always hit , air resistance plays a part without it
Or how good your camera is
You're right I was showing students this experiment by filling balls of the same size with sand and one ball was heavier than other and when dropped from the first floor of the school building both touched the ground at the same time, when one of the teachers made video in slow motion results were not same.
Thanks, Stu & the rest of the Debunked team! I love seeing new content from you. This is a good one, too.
hey I must say it is a pleasure to stumble on a channel that goes in details about questions that are commonly brushed away with a simple but inexact "well known" answer, I am a mechanical engineer and I'm more and more concerned about the false assomptions that are becoming common in the field so thank you for your great work in explaining these phenomenas !!
You can always go into further detail, like the fact that the stated G will be different than real because noone accounted for Gravity weakening with one over the square of distance. G=M1*M2/R^2. Where R0 is the radius of earth, and object dropped.
@@ГеоргиГеоргиев-с3г yes. And the fact that the drag is depending on the velocity is not explicitly said here too. In general it was taken into account here but when he explained the reason for the difference between the steel ball and that heavy blue ball he explained it with a constant force. In fact the drag increases with the velocity. So it is not constant and as the balls get closer to their terminal velocity the difference in the acceleration increases. It is basically a continuous process. All the different forces that contribute to the movement are not really constant but change depending on different factors. The gravity is depending on the mass, which is constant for each ball, and the distance to the ground. However, the distance to the ground doesn't cause a big difference if they are dropped from the same height. It only changes the predicted time until the ball hits the ground. The fact that the drag is depending on the velocity and that this change is much more rapid than the change in gravity is basically the reason why there is a terminal velocity at all. The density of the air is also a factor as he already said at the end of the video.
Bro, I learnt this in detail in primary school ( elementary school if you're American, or under the age of 10)
@@RC-nv6rcmy first when I saw the video title was “didn’t Galileo do that a while back”
Agree. There is more and more stupid in this world and unfortunately much of that is thanks to a bad academic system.
Having said that, this educational video is also built up in a to complicated way and is repetitive. Treating people like they're stupid results in stupid people.
Okay I'm at 3:32. So inertia, if i understand correctly, heavier denser objects have more resistance to change in motion because there are a lot more atoms inside their composition.
And probably every single atom has its own resistance to a change in motion.
And so them more atoms equals more resistance to change in motion because every atom has its own resistance to that change in motion which adds up when put together.
If you slow it down you can see the bowling ball start slightly above the basketball and the bowling ball hits the ground slightly before the basketball. And this is before terminal velocity takes affect.
I could counter that thought by saying the bowling ball is smooth and the basketball is not therefore it will create more drag.
Yes and if you look carefully, you can see he is not standing in a vacuum
Its great to see you implementing real life clips into this video, hopefully we get to see some more irl footage in future videos :)
It's definitely something we're keen to do in future videos, where budgets etc allow. Thanks for watching and commenting!
I enjoyed this, thanks.
Since you already included a brief shot of skydivers, you could also have mentioned that an object that can change the amount of surface area it presents to the air resisting it can influence its freefall velocity. This is exactly what skydivers do in order to catch up to those who have exited the plane before them, and also (more subtly) to stay "on level" with the people they are jumping with.
Just like a flock of birds. Nice.
Great video. This channel is so underrated.
Important calculation is whether the ball will hit the ground before Empire State building security can catch you.
😆 indeed!
One other way to think about it is that the speed of the ball is impacted by two forces - 1) The downward force of gravity 2) The upward (backward) force required to push the air out of the way. These forces cause an acceleration by Newton's Law rewritten as a=F/M. Since the force due to gravity is Fg-Mg them the acceleration caused by gravity is the same for all objects a=Fg/M=Mg/M=g. This is not true for the acceleration caused by the air. That force is not affected by the mass of an object but only its speed and air resistance so since a=F/M, if you increase the mass of the object then the acceleration will decrease and since that acceleration is upward (backward) the object will fall faster. The velocity when this value is the same as the acceleration due to (g) is the terminal velocity since at that point the two accelerations cancel each other out and the object will stop accelerating (its velocity will stop changing).
What if we drop a ball the weight of 10 suns (say some dense stuff like a neutron star) and a basketball.. which will hit Earth first?
That ball would not drop. The Earth would drop to the ball ;-). The basketball would not fall to earth but to the superheavy ball. Earth as we know it and the basketball would be obliterated.
This is THE explanation of non lab fall physics I needed for at least 10ys, concise, easy to understand, well animated, with some IRL footage ontop - thank you.
well, need is an overstatement, and the reason for it is banal, but still, things that knaw at you in the back of your mind after an argument in reallife and/or online. One of these was about a story where a character could change their weight and through that, among other use cases, fall faster, and a lot(!) of people came along with lab-condition rules to claim its lack of realism, totally ignoring air resistance, terminal velocity etc (not that I could explain that well enough, but the argument always was 'that's negligable' .... now I will lead them here :D )
Glad you found it useful! And I totally get where you're coming from. Thanks for watching and commenting! 👍
I would be curious as to what you mean by the character would be able to fall faster. I know if someone told me about a character that could change their weight and was able to fall faster by increasing their weight I would give the same response that the character wouldn't actually fall faster. However that is because the wording makes it sound like if they increased their weight their acceleration would go beyond 9.81m/s^2 which would be mostly incorrect (Unless the character could increase their mass so much that the acceleration due to gravity increased by a noticeable amount). However if you were explaining it more as the character could increase their mass to reduce the effect of air resistance during their fall making their acceleration stay closer to 9.81m/s^2 for longer then I would agree but again that would only be really noticeable in very long falls and most of the time how the character positions themselves during the fall is going to be the main factor in their air resistance.
The objects fall at the same speed in a VACUUM.
If dropped one at a time so that they can't effect each other the heavier object will hit in less time. The only reason it's not apparent with bowling balls is their negligible mass compared to the Earth. For example if it were a case of dropping a bowling ball and a neutron star then the latter would hit first because the Earth would rapidly fall towards it too.
Interesting point, but any situation extreme enough for that to be significant would likely deform the shape of the planet prior to the drop, which I think would actually lower the surface gravity of the planet. Though I’d have to think about this some more.
@@LeTtRrZ I suppose that my point is that although the bowling ball's attraction of the Earth is so small that it's probably less than the width of a proton it's still there, the Earth would still move and by more than with the feather. The reason I suggested dropping each individually is that otherwise it's much like taping the objects together, Earth is being pulled in the same direction by the combined mass of both if dropped together. There's also the point that rather than the objects falling towards the Earth, they and the Earth both fall towards their barycentre, which given the difference in sizes is somewhere very near to the Earth's centre of gravity. It depends on how picky you want to be but tiny effects are still real even if barely significant
1:34 how can i achieve this situation ( what is the proccess to get this type of situation 😅)
Me: I hope this helps...
According to the laws of physics, heavy and light objects fall at the same rate when air resistance is negligible, meaning a heavier object does not fall faster than a lighter one; they both experience the same acceleration due to gravity.
Explanation:
Gravity pulls on all objects equally:
The force of gravity acting on an object is directly proportional to its mass, but the acceleration due to gravity is constant for all objects near the Earth's surface, regardless of their mass.
Air resistance can affect the perception:
In real-world scenarios, air resistance can make it seem like heavier objects fall faster because lighter objects with a larger surface area experience more air resistance, slowing them down more significantly.
Key point: If you were to drop a bowling ball and a feather in a vacuum chamber, where there is no air resistance, they would hit the ground at the same time.
Which do you think will hit the ground first?
At the same time. A simple thought experiment demonstrates this. Imagine a light object tethered to a heavy one. If they fell at different speeds would the lighter one cause the heavier one to fall more slowly or would it cause the lighter one to fall faster?
Hence a contradiction. So they must fall at the same speed.
Edit. The last experiment demonstrates I hadn't taken air resistance into account. 🤦🏻♂️
Shoutout for the conserve ¥ you go to evenpoint, RELEASE the two > 1 falls, the other int even. For mass stays SAME, when releasing some a is byproduct. Descending is in a way faster, for it ultimates in an impact, than orbiting. FASTNESS give by Fg < a,N
In the first situation,(empire state building hight fall, in regular atmosphere) the bowling ball will hit ground first - It's high enough that atmospheric drag would come into play, and I daresay that the basket ball would reach terminal velocity.
However, in a vacuum they'll hit the floor at the same time.
1:30 What's up with the weird cut where the balls are way further of each other but then much closer when hitting the ground? 😂
Lol, you’re the only one to have mentioned it but it bothered the hell out of me in the edit! Bad planning between the wide and close up shots, budget didn’t stretch to 2 slow mo camera 🤷♂️ Thanks for watching and commenting though 👍
At first I was like meh I know this subject quite well. Then I was like ok that’s something new. Great video.
Great that you've filmed your own stuff too on this one!
Thanks, we hope to do it more in future videos - budgets depending.
Could you make a video about which weighs more, a pound of feathers or a pound of bricks. Because I feel like if you gather a pound of feathers, the air in between the feathers will add to the weight. But not sure if that can be debunked. Or maybe if its 100 pounds of bricks VS 100 pounds of feathers, might it then have a difference?
There’s definitely something in that idea 🤔 We’ll have a think about it, thanks for commenting and watching 👍
@@DebunkedOfficial Or instead of feathers switch to cotton. It's probably easier to see if the air makes a difference on regular cotton vs compressed cotton
Which is taller? A 5 foot stack of bricks or a 5 foot stack of feathers?
@@arothmanmusic equal, because length measurements are still. Meanwhile weight & velocity measurements can be affected by air, pressure, and a few other elements like shown in this video
It is important to distinguish weight versus mass. A kilogram (mass) of helium (at ambient atmospheric pressure) has negative weight.
David Scott did this very experiment on the Moon in 1971, on Apollo15. using a falcon feather and a rock hammer, and they landed at the same time. The moon has no atmosphere. There for is a perfect vacuum environment. 😊
So what might be the fastest an object move due to gravity after being dropped? For example a one ton lead filled aerodynamically stable arrow or dart dropped from the space station.
This is actually something under development as a weapon. I think it's called "arrow from god" or "project thor", something like that. Don't remember what speed they would reach, but it's stupidly fast, and has a massive amount of kinetic energy.
It's so weird seeing Stu in a t-shirt. Kind of like seeing your uncle without his token beard.
😆 I don’t actually remember why, but my animated character has always had a white t-shirt on, so I thought I should go with continuity and match as we were bringing the experiment to life. I hope it didn’t ruin it for you? Thanks for watching and commenting! 👍
1:41 Interesting. Only one ball bounced up after landing while the other just stayed in place.
that's cuz it's rubber (elastic) and hollow on the inside so when it hits the ground Newtons 3rd law acts on it (the ground pushes back with the same force) hence it deforms the ball a little and compresses the air inside which immediately pushes back against the bottom and the ball bounces off
@@kami3595 . Ah I see. Then the other ball being not hollow but full and composed of a strong heavy material made it more resistant to the deforming caused by the equal opposite force to it's impact on ground.
Plus no air inside it to be compressed like the bouncy one.
All I know for sure is if you drop a 5-6 week old kitten [onto a pillow, from asafe height], it will land feet first.
1:31 You can clearly see the bowling ball being behind the basket ball but it catches up because of less drag
9:53 The acceleration is not constant as the drag increases as the velocity increases. Purely mathematically the ball will never reach the terminal velocity but just approaches it. Of course in practice there are variations like wind that mess things.
Yep, I hardly ever see this particular point raised. Purely mathematically, terminal velocity is an asymptote. However, like you said, in reality things aren't quite so clear cut, perturbations, cross-winds, hot and cold patches in the air, etc.
A couple of bonus mathematic statements would have rounded this up nicely.
Like drag is velocity squared. How to calculate terminal velocity etc
From 1:31 you can see the bowling ball is slightly higher when released. Yet the frame on 1:34 shows the bowling ball hit at the same time. This means the heavier ball was traveling faster not at the same speed. Yes this is due to air resistance but that was not mentioned at the time.
Best explanation I’ve seen the the topic. Well done
Extremely nerdy footnote:
Even in vacuum the ball with a larger mass will hit the ground first by an extremely small amount without violating Newtonian mechanics. When a mass falls you have to realise that the Earth is also gravitationally attracted to it. The force of the ball on the Earth is the same force of the Earth on the ball (Newton's third law) but the ball accelerates way more due again to the fact that it has very little inertia compared to the planet. That said, the ball and the Earth will both move towards their barycenter (which is extremely close to the Earth's center of mass due to the fact that it has many orders of magnitude more mass than the ball). This means that the ground would move towards the ball by an extremely small amount.
If the ball has a larger mass, the ground will move upwards quicker. Still by a crazy small amount.
If you perform the same experiment in the vacuum twice (just changing the mass of the dropped object) you will see that the more massive one will arrive first 😂
Yes, I don't know why they always miss out on this
But if you drop the two balls side by side simultaneously, as per the examples, then would there still be a difference? The pull of the heavier ball on the earth would also draw the earth towards the lighter ball.
@@MrReasonabubble The Center of gravity would be forced stronger to the ball with more mass, so, no
@@koalamusik yes. But this effect is even smaller than the gravitational acceleration of the earth towards the ball. If there is one airplane flying on the other side of the earth this will already cause a completely different outcome of the experiment according to that. Those effects are so small that you can't measure them. They are only causing a significant difference if the mass of the objects is in a comparable order of magnitude.
@@simsch97 even small effects/forces don't disappear if you want to be 100% precise. And in this theoretical experiment we were talking about a closed system with only one earth and two balls
Going back to the penny drop... What if the balls were the size of the penny (albeit spherical)? The mass is greatly reduced and therefore the air resistance. With that in mind, I would like to think the terminal velocity would be achieved much faster for even the heaviest.
The best science channel on youtube, Veritasium, made a video called "How dangerous is a penny dropped from a scyscraper?" which you might find interesting.
Thanks for the explanation!
Glad it was helpful! Thanks for watching and commenting 👍
To be honest I would love more lessons about physics
I absolutely love gravity. From learning how it is created to Newton and then Einstein. I encourage all to go down the rabbit hole and really learn the fundamentals of Gravity. You won't be disappointed.
Precisely what I'm doing, I would've never came here and searched this if I wasn't studying physics. My understanding completely changed 30 minutes ago when my notes simplified said a=g so I came here lol
another blast content from you guys!! algorithm please hit my fellas up! 🗣️🗣️🔥
Thank you! 😊 we tried really hard with this one to make complicated physics accessible to everyone. Thanks for watching and commenting 👍
08:25f
The 2 heavier balls won't accelerate at the same rate but the heavier ball will accelerate at a higher rate long before the middle ball reaches its terminal velocity.
Applies in a vacuum. A human has terminal velocity of about 120mph, an ant has a terminal velocity of about 4mph.
10:25 that's supposed to be a caricature of Simon Whistler on the right?
Lol, no I’m afraid not. That’s Mark our writer on this particular episode. Thanks for watching and commenting 👍
I tried to tell my teacher not to wake me while I'm sleeping in class because "I'm an object at rest and objects at rest tend to stay at rest" but it didn't work 😂
They tend to stay at rest if not acted upon by external forces ;)
If mass attracts mass, why wouldn't the object with more mass get pulled down to earth faster?
Best explanation ever!. Thks
In a much longer drop, say from 2000 feet, the basketball will hit it's V max much sooner than the bowling ball due to air resistance. From a short drop the difference might be in fractions of milliseconds and would depend on very precise release.
Check out the part from 11:00 onwards
Technically the heavier one is also pulling on the earth by an infinitesimally stronger amount than the lighter one, making it *technically* faster by a tiny, tiny, tiny, amount. But for the sake of simplicity, yes,it is the same.
I waited 15 years for this. Finally a relief.
With or without air resistence?
I love the video. However, I wanted to see you drop balls from actual empire state building.
Explanation at the end of this video may cause confusion, I hope this helps; The air resistans isn't like say 3 Newton, until you reach terminal velocity and you stop accelerating. It will grow along with the square of your speed, therefore it can be easly shown that a lighter object of the same aerodynamic properties will always stay behind, it is hard to calculate the exact differences without a calculator at hand.
I tried using chat GPT to answer the same questions. Taking to account the same parameters it came out with different answers. Why?
Go back and watch the house drop, they don't hit the ground at the same time for the same reason you describe at the 9 minute mark. They are just so close together you think they hit at the same time.
I like this man intonation - it is full of science pasion.🙂
given enough Distance the lighter Object will slow a touch, a drop of a few dozen feet, or many even 200 feet may not show much difference
EARLY and AWESOME video
Thanks! 😊 Did you learn something new?
This is not always true. For example, I find my left ball dropping faster than my right as I age.
🤣🤣🤣
The heavier ball will fall first, because of lighter ball has lower terminal velocity.
I see we’ve reverted to the first style of animation, fair enough, I was starting to miss Stu’s animated alter ego
They both accelerate at the same rate but one got a higher terminal velocity. Also air resistance is a thing and will affect more the lighter/larger object. Didn't watch, tell me i'm right.
Increase the size of the balls until one is the size of Jupiter and the other is the size of Earth. Release them separately and measure the time of takes.
The Jupiter ball will hit the The ground faster. It attracted Earth in it's direction. Using a single frame of reference, it fell faster
5:32 since the two forces pushing up and pulling down are equal at terminal velocity, imagine a world where you would just float in the air, unable to move until acted upon by another force.
What if in theory I had a really really tall vacuum chamber and I drop a heat resistance ball from the top, can it reach the speed of light?
It all depends on the level of accuracy you are aiming for. If you could measure at ridiculous level of billionth of the width of a proton you will see that the balls too has its own gravity, thus they also attract Earth, and heavier object will attract the Earth more.. so even if we remove atmosphere, in reality it is always the heavier object that hits the ground first, but the measurement accuracy is so small it is not even practical.
Thank you so much! Every time I see/here people replicate the thought experiment with vacuum I get the impression that nobody has _actually_ thought through the test setup and result. They all treat the ground as a fixed reference frame and use objects with pretty similar masses. But what if one of the test objects is, say, the moon?
The point of this experiment as I understand it is to show that it is not the objects _own_ mass that _causes_ it to fall. But the time till it hits the ground should still depend on _both_ involved objects because the really fall towards each other.
I am NOT a physicist, maybe I am missing something.
In the vacuum, objects fall at the same speed. True, the heavier object pull is greater, but so is its inertia, which makes it harder to move. And it turns out that these two effects cancel each other out.
which will fall faster in air, a metal ball or plastic ball (same size and same smoothness of the surface). If different time then why ??
Was expecting you would include the Apollo 15 demonstration with the hammer and feather.
this video in 12min taught me what my uni physics professor couldn't in multiple 2.5hr classes/labs
Commenting before watching ... I think they'd hit the ground at the same time if dropped in a vacuum... but with wind resistance affecting a basketball more than a bowling ball, over a high drop, the basketball may skew more to the side and take longer to drop.
I know that in a vac they'll fall the same, but air resistance slows the lighter object slightly
I'm sure people forget about them falling the same...in a vacuum
Fun Fact, The feather and bowling ball was actually recreated on the moon during Apollo 15. Except he swapped out the bowling ball for a rock hammer.
This was performed by Commander David Scott, not only that, it was broadcasted live on TV.
It indeed demonstrated that both items, within the vacuum of space, fell at exactly the same rate and landed at the same time.
Pretty cool if you ask me 🙂
We actually include the NASA footage of this in our video 👌
@DebunkedOfficial which part of the video exactly? Yes you included footage of 'an experiment' done by NASA, the one inside a vacuum chamber here on earth. I was referring to the one done on the moon during an EVA on Apollo 15 in 1971. It was done for publicity, mainly to get kids enthusiastic about science.
@@DebunkedOfficial I was refferring to the experiment they did on the moon itself. Not in a vacuum chamber here on earth.
tl;dr
yes, but to a point, everything will eventually hit terminal velocity if given enough height and time. though the object that achieves it faster will obviously be further down
All objects have different terminal velocities
In vacuum everything falls at the same speed. As simple as that. There was a little bit of a popular science demo when one of the Apollo astronauts on the moon dropped a hammer and (i think) a feather and they fell at the same speed..... and that's not because of 'the moon' but because of 'the vacuum'.
The two object will have different terminal velocity so if you drop it the a high enough height you should see a different.
Only true nerds wouldn't know the difference between a bowling ball and a basketball 😝
BANGER!!
So gravity alone doesn’t intensify the gravitational force based on the weight and mass of an object but atmosphere AKA air does give resistance and has a greater effect on lighter objects because of a lesser weight and velocity on air molecules. I think somewhere in this experiment is the answer to why super massive black holes at the centre of galaxies propel stars around it evenly throughout when again our intuition would have us believe stars closest would be more affected and orbit faster.
Guess I'm just dumb but I'm not grasping how "inertia" of a heavy object means it's going to be harder to stop it's fall, combined with gravity accelerating that object's fall, results in any cancellation of forces ????
Question about finding the heavier object's terminal velocity: Why not instead of increasing the height, you just start with a greater initial velocity like -100m/s at t=0 instead of 0m/s at t = 0?
Question:
Why snake venom is much stronger than it needed to kill it's prey instantly. How the snakes around different places of same species have difference in there venom compositions. Example Inland taipan
Also, if the object is small enough, bouyancy effects might come into the picture. For objects the size of a pea or at the very least a grain of sand, I don't think you will get the same result. I am glad rain drops don't fall at the speeds described in the video!
Basically the heavier balls have a higher speed cap and better gravity, but inertia compensates, but gravity increases and inertia does not, but the basic balls have neither of them.
Also too, air resistance doesn't change.
I love this video it is great.
How high does a basketball bounce after being dropped from the Empire State Builduing, please?
I suppose it's high enough for it to reach its terminal bounce velocity :D
Perfect! I was happy to see that the interesting effect of the air resistance and terminal velocity was not walked around. This is the complete story.
Bro tried to sneak in V-sauce and thought we wouldn't notice
They will hit the ground at _almost_ the same time. In the absence of atmosphere, they would land at _exactly_ the same time because gravity acts on all mass equally. However, due to atmospheric drag, the lighter of two equally sized objects (in this case, the basket ball) will hit the ground slightly after the heavier.
The difference from atop the Empire State building between a basketball and a bowling ball would ultimately only be a fraction of a second. However, the difference would be significantly more noticeable if you were to compare an iron shotput and a whiffle ball of equal diameter, or if you were to drop the two balls from a more significant height.
In Vacuum: Give one of the test objects the mass of the moon and don't treat the earth as a fixed reference frame. Do both test objects hit the ground at _exactly_ the same time?
@@carstenbohme8813 Excellent. The ball with the mass of the moon will surely attract the earth, but the other basket ball will benefit of it too.
But the moon ball will also attract the basket ball, and this will totally disrupt the "equality of fall time"
And even further, with a ball of the size of the basket ball but with he mass of the moon, many relativistic effects are expected!!!
So, if each ball was dropped from the height needed to achieve their respective terminal velocity and were dropped at the exact same time, would they hit the ground at the same time?
That’s what we originally thought would happen, but from a height like this that is not the case. Watch it again from 08:35
the balls don't accelerate at a constant rate. as the velocity increases, the air resistance increases, so the ball's acceleration gradually decreases until it hits 0.
That’s why parachutes don’t work on the moon despite having low gravity. Air resistance can also generate heat if objects fall at a much greater height such as a meteor which falls to earth at the minute it enters our gravitational pull.
Additional (or instead): Do *denser* objects actually fall faster than light objects?
*Sentence case* seems more suitable to "question titles" like this.
You can't debunk a *question!*
ýes its true that the weight doesnt effect how fast something is dropping but the air resistance does. becausse the bowling ball is smaller it automaticly makes it the object that will hit the ground first if let go off at the exact same time, dropping it by hand from 2 meters high while cutting the final drop multiple times is the most unscientific way to show it
Leonardo da Vinci disproved this nearly 600 years ago at RISK of HIS LIFE for "heresy" against the Catholic "Church"! He dropped a small cannon ball and much larger and heavier cannon ball (NOT from the Tower of Pisa as the myth goes) from a height of about 400 feet and they hit the ground simultaneously. That's how he GREATLY improved the science of exterior ballistics (accuracy) of the cannons. My lab partner and I proved it in my Junior year of High School Physics I on the third floor of the Old Central High School in downtown Tulsa in 1969 with ball bearings dropped down the stair wells three floors. We also proved the Earth is round and calculated it's diameter to 1%, how long an "hour" is, that the Earth moves around the Sun, the size of a molecule, therefore an atom, and LOTS more!
Gravity is based on size and expansion not mass and attraction. Gravity is simple Galilean relative motion. The earth is approaching- expanding at 16 feet per second per second constant acceleration- the released object. “The Final Theory: Rethinking Our Scientific Legacy “, Mark McCutcheon for proper physics.
Why complicate that much?
The one that will hit the ground first is the one with less air drag, doesn't matter the weight. Given the time and velocity necessary for it to get in action.
Very good but incomplete. let's says I add a fourth ball of a *mass* of 1g. I really means 1 gram of mass. A typical basket ball volume is 7 liter (yes, I checked twice, r=1.19 dm =>7 liter ). So filled with helium, 1 bar at 20°C , 0.1g / liter we have 0.7 gram, plus 0,3 gram of rubber => 1g.
But the density of air 1bar / 20°C is 1.2 g /liter, so 7 liter of air is 7* 1,2 = 8,4g.
So the 4th balloon got a Archimedian up force of 0.0084 * 9.81 N , and a gravitational force of 0.001 * 9.81 N-> *it goes up!*
All of that to explain that archimedian force is here too.
If we want to be perfectly exact, we need to be careful with the term *weight* . Because the real definition of the weigth is "on the location of experience, the *force exerced by the still object on the ground* ". And this is *not* exactly equivalent of "the force of gravity exerced by the planet on the object".
For example, the weight at Quito is the result of 3 forces:
- the gravitational attraction of the earth on the object
- the centrifugal force created by the earth rotation (it is not so small, at the equator 0.03 m/s², nearly 0.3% of the gravity)
- the Archimedian force
So, in the air, 1kg of lead is heavier than 1kg of feather. Because the net volume of 1kg of feathers is bigger than the volume of the lead, so the archimedian force is bigger.
To effectively measure that, you have either to measure the 2 masses in the vacuum, or to measure the mass by it's inertia, not by weigth. :D
There is even one other factor in your experience. It is coriolis effect. It will not measurably change the time of fall, but it may measurably offset the location on the ground.