Center of Mass
HTML-код
- Опубликовано: 11 сен 2024
- Center of Mass and stability demonstrations
It is useful to note that the mass-center is a fixed property for a given rigid body (e.g. with no slosh or articulation), whereas the center-of-gravity may, in addition, depend upon its orientation in a non-uniform gravitational field. In the latter case, the center-of-gravity will always be located somewhat closer to the main attractive body as compared to the mass-center, and thus will change its position in the body of interest as its orientation is changed.
In the study of the dynamics of aircraft, vehicles and vessels, forces and moments need to be resolved relative to the mass center. That is true independent of whether gravity itself is a consideration. Referring to the mass-center as the center-of-gravity is something of a colloquialism, but it is in common usage and when gravity gradient effects are negligible, center-of-gravity and mass-center are the same and are used interchangeably.
Excellent explanation with practical approach. The best video on this topic!
Here in India we like your lectures a lot.great clarity.sir...Love from India
I learnt a lot about centre of mass. I would definitely apply these demonstrations to my students. Thank a lot Sir
After hearing people explain why men cant do the 'chair challenge' but women can, I had to find out the real reason and how to explain the difference.
Thank you so much, my brain feels at peace again. Lol
Really you have done a great job , I am really proud of you , in 2 years I am gonna be physics teacher and I hope to be as good as you and have that same ambition
Oshy Chan so are you a teacher now?
@@Zuhaib_0 🤣🤣
now you've been teaching since 4 years !!
It's been 5 years now!!!
It's been 6 years now
Thank you. I love this. It really gets the concept across. I'm teaching Calculus 3 students how to use multiple integrals to calculate the coordinates of the center of mass of an object. The textbook is full of formulas and details, but I wanted to open with something more conceptual. This is perfect.
very nice ...thanks for this ...I went back to this old school logics before I prepare myself to order an outdoor Almirah with wheels underneath. And this video has certainly helped !!
Que bueno Sr. David!!
Really good Mr.David!!
Gracias thanks merci....grazas
Muy interesante la explicación con cosas sencillas. Muchas gracias. Seguiré viendo sus videos. Saludos desde aqui Lima Perú presente...
You are an amazing teacher ,and must be a good human too :)
Yeh probably he is
To account for that, you could put a nail in the "thickness"or z axis side of the block and use a weight on the end of a string to find the line where the center of gravity must lie. Then, if you know the center of mass for the block if it were of uniform thickness (the center of mass for the x and y axis), you find their intersection.
Thank you a lot. I am in 9th grade and my concept got clear because of you. Thank You.😁😁
I APPRECIATE YOUR EFFORTS SIR! A PRODUCTIVE 10MINS FOR MY EXAMS,THANKS A LOT!
REMEBERING THIS VIDEO WAS A DECADE BACK,WOAHHH!👌
You're a genius!! Thank you SO much for this!
7:12 rockets only use rcs thrusters for docking, for stability they use gimbal in the main engine.
Thank you.
I stand corrected on how a rocket keeps the center of mass above the propulsion force. Here's a video demonstration of how the gimbal can alter the direction of the rocket's thrust. ruclips.net/video/7196ru3wpjA/видео.html
Wow a spectacular explanation. Thank you sir👏🏻
This is an amazing method of explaining a physics topic !!
Very well explained Sir
Just awesome. Thanks for the video.
Excellent explanation
Your explanation is above of excellent
Thanks. It helped me understand
Really good video! Learning this stuff now in college!
The best explanation ever !!
Dear Professor,
Terrific ! I've understood "center of mass" after watching your video ! Thanks a lot. But I have one question: I've read about the mass of center or "barycenter" of the earth-moon system; it is somewhere inside the earth ! In your video, the mass of center in inside only one object ( a piece of wood, a plastic bird or a rocket ......) whereas the earth and the moon are two totally different objects thousands miles away with no connection. How can they be considered as an object to have a common center of mass ?
Silly Jack.
Centre of mass among two particles can be calculated...
VERY WELL EXPLAINED SIR....
❤❤ amazing teaching technic❤
you are a very goooooooooood teacher thanks
Your the man David.
This is an amazing video thank you so much!
Very nicely explained! Thanks!
Wow!!!!
Nicely explained Professor!
This is gold Sir
super experience of support is given for me
you nailed it.
Very good!!!
Thanks for the demo
First of all, you are really very good sir and your videos are the most beneficial for practical explanation to elementary level students!
Now my question is, does center of mass/gravity location depends upon the density of the material, and so the stability of that object? For example, I have a stick of wood and a same size stick of Iron, so, will there be any difference between the center of mass? Also, will it effect the effectiveness of balancing them on hand like you did with the broom stick?
Hello ***** , irrespective of the density of the material if should have the same center of gravity and mass provided it has the same material throughout. That is to say, the equilibrium point is dependent on the geometrical shape (that is only when it is the same material)
Can you explain mathematically why we can always find a line through a lamina (eg a horizontal line y=a in some coordinate system on the lamina) such that the moments on either side of this line sum to zero. It's intuitively obvious physically (hanging plumb lines etc) as you describe here but I just can't prove this mathematically. The mathematics involves the integral of all the moments of every point mass of the lamina on either side of such a line, putting this integral equal to zero and solving for the coordinate of the centre of mass. But why can we always assume we can put such an integral equal to zero in the first place.
hello proffesor what do call that string?
Excellent explanation
Excellent
Good
Thanks mate! Your video is amazing!
cool video..............
What is the geometrical correlation between the shape and the downward force if gravity?
Nice one....
So is center of mass us the same as center of gravity for at least objects at earth?
Awesome thank you so much
nicely explained ,,,,,... :)
Thanks. Good video.
Beautiful 😍.. I love you Physics
Nicely explained
thanks bro
very helpful video thank u...
excellent....
that's good coz you re tching us more things than what we know
Great. But, I would like to ask what if the thickness of wooden blocks shown in the first two experiments (regular and irregular shapes) is not uniform? Where is the centre of mass by looking at 3-D model?
great vid
it was just amazing to hear you !!! ,thanks a lot !!!
Amazing
so, in the last experiment, if you'd placed a golf ball (a heavy one) in the cup instead of a ping pong ball, the cup with only water would've tipped first, right?
Yes, that's right. The c.o.m. would be lower and the cup would be more stable with a golf ball in the bottom. An extreme example of this would be the keel of a sailboat - very large mass at the bottom of the boat making it difficult to tip it over.
@@davidtaylorfuhsd thank you so much for the answer Sir. This video is just brilliant.
excellent
A lifesaver
👍👍👏👏🙏
Is center of gravity just force down but isnt same as center of mass
That really helped :)
This is the closest to magic I have witnessed
It’s so fascinating
Bit confusing because you keep changing between the terms center of mass and center of gravity. Otherwise nice demonstration.
At 9:12, both the cups do not have the same volume of water right? What does the ping pong ball do, that makes the centre of mass higher in the cup on the left?
Since there is no water inside the ping-pong ball, the center of mass of the water is higher. The amount of water is less, but the "point at which all the water's mass seems to be" is now higher than in the cup without the ping-pong ball.
but why? Another concept I don’t quite understand is how an object’s center of mass can be outside the very object itself. ( the Fosbury flop )
good
Physics is awesome
Am I the newest person to watch this?
I don't think they have the same amount of water because the ball takes some of the spaces in the cup. You need to measure the water first and put equal amount of water in both cups.
+TES HAI It is the level of the water that is the same and not the actual volume of water. The fact that the ball takes up space with air is what causes the center of gravity to be higher in the cup with the ball.
Thanks for sharing! Those are some great center of mass demonstrations!
But the cups don’t have the same amount of water
7:00 This would make an interesting practicle...
That's not teaching that's art..
the center of mass of an object is in the center
is there a difference between center of gravity and center of mass?
It is useful to note that the mass-center is a fixed property for a given rigid body (e.g. with no slosh or articulation), whereas the center-of-gravity may, in addition, depend upon its orientation in a non-uniform gravitational field. In the latter case, the center-of-gravity will always be located somewhat closer to the main attractive body as compared to the mass-center, and thus will change its position in the body of interest as its orientation is changed.
In the study of the dynamics of aircraft, vehicles and vessels, forces and moments need to be resolved relative to the mass center. That is true independent of whether gravity itself is a consideration. Referring to the mass-center as the center-of-gravity is something of a colloquialism, but it is in common usage and when gravity gradient effects are negligible, center-of-gravity and mass-center are the same and are used interchangeably.
@@davidtaylorfuhsd thanks for the explanation
he looks like he is doing this on gunpoint
Although the title says "center of mass", he keeps talking about "center of gravity". Even tough, they could be in the same spot, they are not the same. This video did not help me at all.
+Roberto Ganoza www.quora.com/Whats-the-difference-between-the-centre-of-gravity-and-the-centre-of-mass
u talk about cog and then ur title is com.....hmmmm...it is not the same
For these objects it is.
#vov prof.
4:04
Confirm one more view from😅🇰🇪
Ok
aren't you confusing Center of Mass with Center of Gravity
In our experience here on Earth with the objects most of us deal with everyday, the center of mass and the center of gravity are in the same location. Very large objects where the pull of gravity can be different on the same amounts of mass due to the large distances involved, are not encountered in our everyday life.
@@davidtaylorfuhsd ok
😘
Plum bob
Mr Chen Sent Me Here?Anyone Else?
online homeworkkkkzzz...