Fr0st1s Well, I thought that was normal, they put up Science, History, Math or English videos from the State Governments eLearn systems, or RUclips, go through it with us, then we do the normal school stuff like typing our assignments and notes and points and study guides on our laptops, that data helps us complete our course assignments for each semester, the data is imputed to the National OneSchool system which pretty much governs all public schools in Australia, It's quite high tech when I think about it now, easier than what America and other poor people countries do.
WOW! Australian school system looks so advanced. Now to think of it, I feel like I finished school in stone age, compared to you :) Even today education system in my country looks is poor.
Suddenly I'm actually glad I took AP Calc because when he started talking about the rock that started at escape velocity getting slower and slower but not stopping I was like "Oh, you mean a limit?" and it made the whole concept easier to get. So much for never using it. lol
I agree. I understand everything he was talking about, but that is because I already knew this stuff. If I were unfamiliar with orbital mechanics the lack of visuals could be really confusing.
I never understood this RUclips thing of a video in which you only see a person talking to you. Completely ignores everything that would be possible with video.
Astronomy class was one of the few I looked forward to in high school. Classroom in a planetarium every day, watching the stars spin by while listening to Stairway to Heaven...this isn't like my class, but it's kept me as interested as I have been in that room for my high school career. Really glad I found this series from the start, and I won't be stopping until you guys do, which hopefully is in a VERY long time :)
Sayuas It is, but I'm sure we'll get into the good stuff later on. Actually explaining what gravity is is more astrophysics, which I'm sure he'll get into later on.
Your videos are highly educational. You and the rest of the crash course team make education fun and interesting to learn. Keep it up. Don't forget to be awesome crash course.
I really wish he would do a series showing how to actually measure and calculate luminosity, distance between celestial objects, blue/red shift, etc. In simplification, it would be amazing if he had a series specifically dedicated to cosmology.
OMG, I love that Douglas Adams definition of flying. I have been laughing with it for years and now I know why it is also cientifically accurate. Thank you!!!
I love his explanations for things! Just when I'm about to feel like I can't wrap my head around it, he says something that will simplify it :). Go Phil!
I have watched a lot of these crash course, and this is one of the best I have seen. You teach very clearly, and have a very engaging style. My hats off to you sir!
just started watchin' this, had a lecture about gravity and black holes today and saw it is exactly a year since this video was posted. Thankyou, crashcourse, for making Astronomy videos :)
kake pynt If you're 50% of the views that means they only got 2 viewers. That's not a very good incentive. Maybe they should make a crash course math/statistics instead.
These episodes are amazing. Thank you so much for broadening my, and many other people's minds. Space is so fun and helps with perspective. Thank you :)
Wooow. This is actually great. I remember last year where we talked about the difference between mass and weight in class. One of my classmates said that mass is weight not influenced by gravity while weight is mass influenced by gravity, and my teacher agreed. Wew. Don't know how that happened. Good thing I watched this vid. Thanks
can you guys clarify how it maintains its orbit if gravity is bound to pull it in? What causes that orbiting suspension? sorry for this question, i really haven't got into science that much because of my chosen course.
If you think about it in terms of general relativity, then there is just a line in space time that wraps around the Earth that the moon is following. But thinking from the way described here, the moon is falling towards the Earth. Imagine throwing a ball so far that it goes around the apparent "edge" of the Earth. You would see the ball come back around as it continued to try and fall, only to miss the Earth by the time it gets to a height where it would normally land. This perpetual falling is how the moon stays in orbit, just farther away.
You'll probably discuss this in the next video, but wouldn't it be better to say that gravity *is* the warping (curvature) of space, rather than it *does* warp or curve space?
This was my one nitpick of the video. Gravity IS the warping of space-time, is doesn't cause it. A subtle difference that doesn't make the video any more confusing to people who are struggling, but makes it correct.
There should be a Crash Course Maths, or rather, Crash Course Calculus, Crash Course Linear Algebra, so on. Why is it that there's no Crash Course on Maths?
i think crash course calculus would only be good for a few episode, i can't imagine a level and degree level maths making great youtube videos but id love a mathematics series
Crash Course has a limited amount of resources to make videos. It's possible they'll get to math some point in the future. Khan Academy and plenty of other websites have lots of good math videos right now if you are interested in that.
All I have to say is that you guys are f***ing awesome for posting all this incredible info in an easy to digest format for everyone!!! keep it up you guys rock.
Wow, this is the third time someone has explained this to me in less than 12 hours! First my physics teacher, then Randall Munroe in What if, which I was reading during my lunch break and now Phil... I'm sure not going to forget this any time soon : )
Jacob Shepley Not per se... mechanical engineering is all about loads on structures. That and temperature. So a quick video describing how maximum loads are calculated would be nice.
As they always say in the science class, "no question is silly". The escape velocity of universe depends on which direction you want to escape and what gravitational force is in your way. If earth is the only object then your escape velocity is more than 11km/s and if there are more planets then you calculate the gravitational force according to the angle of the gravitational force minus the gravitational force of the planets ahead of you (which are pulling you in) according to their angle compared to your position.
there's no length, breadth, height, or time, or anything outside the universe, so yea...and the universe is expanding at pretty darn fast rate..theories say that going to the edge of the universe doesn't really take you to the end, in fact, if you keep going, you'll reach where you've started. kinda like going around the earth..
True, but I'm talking about normal conduction, which is universe is not moving or expanding and all the mass in the universe does not change or move. Same calculation as when we calculated the force at which two or multiple protons place on one another. In physics class when we calculate two trains moving towards each other, we are not considering the air resistance, wind speed, and friction. It makes the calculation hard and also discourages people from understanding the basic concept.
I don't think it's possible to calculate the escape velocity of the universe because we do not know its exact mass. We can estimate the mass of observable universe, but that's just the portion of space 13.8 light years in all directions from Earth, and there is probably more stuff beyond that.
Probably a silly question, but Planet Earth has more mass than the moon, so why does it not pull it into itself or does the Earths circular velocity throw it out? I can't think of another way to describe it.
well, the moon was formed after the earth collided with an object of roughly the same format. Maybe the millions of small particles (which later formed the moon) were blown into space, and were constantly falling (on 4:20 phil explains that)
Arnold Robert Lee The Moon is orbiting the Earth. Just like the Earth is orbiting the sun. So the reason the moon doesn't crash into the Earth is the same reason the Earth does not crash into the sun.
For anything to fall down to earth (assuming the earth is motionless), all of its momentum (motion) has to be toward the earth. Consider the example of the ball. If you drop a ball from a height, all of its motion is in the downward direction (toward the earth). But if you give it a sideways push, it will still fall down but will land in a different spot because its motion is now in two directions: one is vertically downward toward the earth, the other is sideways, away from the earth. It just so happens that in this case, the downward motion is more powerful than the sideways motion. Hence the downward motion eventually wins and the ball hits the earth. However, if you give it enough sideways motion, the two motions will balance each other and the ball will get stuck. Its downward motion tries to bring it toward the earth but its sideways motion tries to take it away from the earth. And since the two are equal, the ball ends up doing neither. In other words, its distance from the earth doesn't change, which happens to be the definition of a circular orbit. I hope this helps. Btw things are a bit more complicated in reality because there are many more forces involved but this is essentially what happens. Hope this helps.
This is honestly the most mild and reasonable comments section on RUclips, the questions are reasonable, the arguments are sound, and for a science video there was no mention of religion or your own personal beliefs. (From what I've seen)
The escape velocity of what is 11 km/s? You're saying that a marshmallow and a sport stadium would need to reach the same velocity to escape Earth's gravity? I guess it has to do with the acceleration due to gravity. Never thought that the escape velocity would be the same for all masses ("escape acceleration" would be different though I do believe).
Yes! But see, as he described with regards to mass, it would take a LOT more energy to get a stadium collectively up to 11 km/s than a marshmallow up to 11 km/s. Think about it this way: Voltron rockets off of Earth to its escape velocity of 11 km/s. Then, Voltron stops accelerating. At this state, the Cats-Bot is shooting away from the Earth without needing to speed up any more. Then, Voltron separates. What speed is each of the five wildcats traveling at? That's right, they're each still traveling at 11 km/s away from Earth! The speed of an object is not the same as the energy put into it. The speed is related to the energy put into an object, as well as the mass of it. P.S. BY THE WAY, Earth has an atmosphere. Even though you can build a marshmallow shooter that can pop out marshmallows at 11km/s, the marshmallow slows down due to air resistance far before it can escape the atmosphere. And shooting the marshmallow away from the Earth at a higher speed so that it would slow down to 11km/s when it reaches the edge of the atmosphere...would vaporize the marshmallow before it even got there. :(
This is where things get confusing for me. I just don't understand mass and velocity. But still good to learn about it!! Another great video in this series!
SPOILER ALERT Gravity isn't a force. It's all about curves ;) EDIT: Sorry guys, a lot of what you deliver is great and of a high quality standard, but this was just poor. I'm sure this video was aimed for a particular audience but you could at least mention that the best theory of gravity we have (Einsteins Relativity no less) demonstrates that Gravity isn't a force and that its really about the curving of what can be thought of as a 4D mathematical space and then reassure viewers to just think of it as a force for the sake of this video (you know, to keep things simple). When you mentioned that gravity warps the space around it, close, but that would be that mass warps spacetime (relativity again). For those interested to know, gravity is NOT a force and really everything just moves in straight line vectors within the curvature of spacetime - spacetime being curved by MASS. Gravity doesn't bend light, mass bends spacetime and photons still travel in straight lines within a curved space (not light travelling in curves in a flat space). Also, please excuse my avatar, I am a liberal and believe in peoples right to choose. Although I don't partake as much as I once did, it was blazing that got me fascinated and literally opened my mind to theoretical physics... dude.
docopoper Well, probably? But why would we need FTL communications before some kind of FTL or Near-FTL form of propulsion? I guess it would fix the problem of Time Delay for a while, but it isn't that.. well, useful
A zillion light years is an distance, not a period of time. You are confusing it with looking back in time when observing a star that is a certain amount of light years away.
Wow, I didn't find anything to nitpick this time. Everything was really carefully phrased. Actually, it almost sounded a bit forced ... hey, that was a joke! It was a joke, ok?
Gunflower, Earth is a planet! So are Mercury, Venus, Mars, Jupiter, Saturn, Uranus and Neptune, as well as thousands of similar bodies orbiting other stars
I'm the owner of the profiles son and we home school. These videos are the best! I love these.Every time my mom says to watch a video on something I ask for a crash course vid! Bye!!
No matter how many times I hear a science educator explain gravity, it still makes me giddy thinking about how people listening/watching will have their minds blown.
FUCK, I JUST REALISED SPACE IS CALLED SPACE BECAUSE ITS EMPTY SPACE WHY DIDN'T THEY TEACH THAT SHIT IN SCHOOL ARRRRRRRRRGH FUCK MY LIFE UGGGGGGGGGGGGGGGGH
i enjoyed this video and the graphics really helped me. more graphics the better. i understand the gravity weakness inverse ratio better than before due to the graphic. Thanks.
Thank you for a great explanation. It helps me understand more about gravity. I wish you make a video about vectors in one dimension and then two dimension. Once again, thank you for a great lesson.
Next on CC Astronomy ...Meteor showers!!! Yeah? Can we get that maybe? Next after Tides that is. That should be a good episode :) This series is awesome, I love it!
Will you also be talking about how swing-by maneuvres work? I think I have figured it out (gravitation is acceleration; and that's speed change over time, not over distance; so you get accelerated more while flying to whatever body is used for the maneuvre than you get decelerated while flying back away from it) but it would still be very interesting to see that confirmed (or corrected!) in more depth and detail =) And since with deep-space exploration becoming bigger a thing, paired up with faster and faster computation (thus allowing more and more complex flight paths), swing-by maneuvres are bound to become even more and more important (well, until we get warp drive or something), I guess this topic might interest many viewers!
I’m mad because this video is too informative I can go on and on writing notes on this video w vid thanks sir your an great teacher thanks for the help
If I was a science teacher, I would feel compelled to show each of these videos for 10 minutes per class. They're amazing
they do in australia
Khan Piesse You guys are so lucky!
Fr0st1s
Well, I thought that was normal, they put up Science, History, Math or English videos from the State Governments eLearn systems, or RUclips, go through it with us, then we do the normal school stuff like typing our assignments and notes and points and study guides on our laptops, that data helps us complete our course assignments for each semester, the data is imputed to the National OneSchool system which pretty much governs all public schools in Australia, It's quite high tech when I think about it now, easier than what America and other poor people countries do.
WOW! Australian school system looks so advanced. Now to think of it, I feel like I finished school in stone age, compared to you :) Even today education system in my country looks is poor.
Fr0st1s
What country is that?
Suddenly I'm actually glad I took AP Calc because when he started talking about the rock that started at escape velocity getting slower and slower but not stopping I was like "Oh, you mean a limit?" and it made the whole concept easier to get. So much for never using it. lol
You're an awesome teacher! I love how engaged you are, it makes me feel like I'm watching Bill Nye again
hahaha,
he is my best astronmy teacher .
kareem mostafa
If I might make a recommendation, oh fellow astronomer, I would suggest more graphics for things like the shapes of orbits and whatnot.
I agree. I understand everything he was talking about, but that is because I already knew this stuff. If I were unfamiliar with orbital mechanics the lack of visuals could be really confusing.
my thoughts exactly
I never understood this RUclips thing of a video in which you only see a person talking to you. Completely ignores everything that would be possible with video.
Astronomy class was one of the few I looked forward to in high school. Classroom in a planetarium every day, watching the stars spin by while listening to Stairway to Heaven...this isn't like my class, but it's kept me as interested as I have been in that room for my high school career.
Really glad I found this series from the start, and I won't be stopping until you guys do, which hopefully is in a VERY long time :)
6:17 that part was funny like
“I hope you kissed your rock goodbye because it ain’t coming back”
I like Phil he is funny
This brings me flashbacks to physics.
Gotta say, I got more out of this video than an entire lecture or two of physics on gravity.
I'm in college dude xD
I changed to IT.
This is all really basic, I was hoping for more advanced stuff.
I bet he'll build upon this stuff later on :)
Probably going to be a 30-40 episode series, so what I said seems plausible
Sayuas It is, but I'm sure we'll get into the good stuff later on. Actually explaining what gravity is is more astrophysics, which I'm sure he'll get into later on.
Your videos are highly educational. You and the rest of the crash course team make education fun and interesting to learn. Keep it up.
Don't forget to be awesome crash course.
I really wish he would do a series showing how to actually measure and calculate luminosity, distance between celestial objects, blue/red shift, etc.
In simplification, it would be amazing if he had a series specifically dedicated to cosmology.
OMG, I love that Douglas Adams definition of flying. I have been laughing with it for years and now I know why it is also cientifically accurate. Thank you!!!
Great job guys, this is proving to be another wonderful CC. They enrich my life immensely. Genuinely can't thank you enough.
For me, this is more informative on the topic of Astronomy than even the Cosmos series. Home. Freaking. Run. Phil, you da man.
I love his explanations for things! Just when I'm about to feel like I can't wrap my head around it, he says something that will simplify it :). Go Phil!
Easily my favorite Crash Course series so far. KEEP IT UP!
4:29 I IMMEDIATELY Thought of Toy Story when he said that
Woody: THAT WASN'T FLYING! THAT WAS FALLING WITH STYLE!!!
Me too :)
are you okay?
I have watched a lot of these crash course, and this is one of the best I have seen. You teach very clearly, and have a very engaging style. My hats off to you sir!
Hey! I uploaded a science video back in July with this same exact title! ...great minds think alike?
Whoa, dude. Fancy seeing you here. :)
just started watchin' this, had a lecture about gravity and black holes today and saw it is exactly a year since this video was posted. Thankyou, crashcourse, for making Astronomy videos :)
Can you start
Crash Course: Geography
Pleeeeeeeeeease
I'll give you 50% of the views
+ i did not write first so you should do it
kake pynt If you're 50% of the views that means they only got 2 viewers. That's not a very good incentive. Maybe they should make a crash course math/statistics instead.
Heard of refresh.........
That would mean they would get two views.
Haven't you ever hear of CGP Grey?
Best Crash Course Astronomy so far, really looking forward to the next ones!
Crash Course Physics!
might have to be more specific, after all, everything is physics!
Edward McDOnagh Yes, I am quite aware of that fact. However, Physics textbooks do exist. How else am I supposed to explain that?
McKenzie Banner This is physics. You will have to be more specific.
It is available now!
why do they never discuss terminal velocity when gravity is discussed
you are the best teacher who teach astronomy science
Looks like we're going to learn about gravitational lensing!!!! Fun
These episodes are amazing. Thank you so much for broadening my, and many other people's minds. Space is so fun and helps with perspective. Thank you :)
I'm starting to get into astronomy, thank you for that Phil, keep on keepin on
Wooow. This is actually great. I remember last year where we talked about the difference between mass and weight in class. One of my classmates said that mass is weight not influenced by gravity while weight is mass influenced by gravity, and my teacher agreed. Wew. Don't know how that happened. Good thing I watched this vid. Thanks
So what you're saying is; the moon is literally just falling at the Earth and missing.
Weeeeird.
Yes. Not weird, truth.
electrocat1 the truth can be weird.
can you guys clarify how it maintains its orbit if gravity is bound to pull it in? What causes that orbiting suspension? sorry for this question, i really haven't got into science that much because of my chosen course.
If you think about it in terms of general relativity, then there is just a line in space time that wraps around the Earth that the moon is following. But thinking from the way described here, the moon is falling towards the Earth. Imagine throwing a ball so far that it goes around the apparent "edge" of the Earth. You would see the ball come back around as it continued to try and fall, only to miss the Earth by the time it gets to a height where it would normally land. This perpetual falling is how the moon stays in orbit, just farther away.
So then, what's keeping the moon from falling? in terms of force that is.
Hey Phil, just wanted to say that I think you're killin' it with this host gig. Keep up the good work!
You'll probably discuss this in the next video, but wouldn't it be better to say that gravity *is* the warping (curvature) of space, rather than it *does* warp or curve space?
baby steps Matt. baby steps. Remember that many out there still struggle remembering the names of the planets.
Arturo Gutierrez That sickens me.
This was my one nitpick of the video. Gravity IS the warping of space-time, is doesn't cause it. A subtle difference that doesn't make the video any more confusing to people who are struggling, but makes it correct.
This is awesome! I loved you badastronomer channel since day one!
There should be a Crash Course Maths, or rather, Crash Course Calculus, Crash Course Linear Algebra, so on. Why is it that there's no Crash Course on Maths?
i think crash course calculus would only be good for a few episode, i can't imagine a level and degree level maths making great youtube videos
but id love a mathematics series
I wouldn't expect them to delve in deep but single-variable calculus is reasonably simple. It may as well be Algebra or a particular topic of Algebra.
Crash Course has a limited amount of resources to make videos. It's possible they'll get to math some point in the future. Khan Academy and plenty of other websites have lots of good math videos right now if you are interested in that.
Dan Heidel I don't think it's more expensive than their usual videos. There's MIT Open Courses also, it's just a thought really.
That would be great! I'm not in calculus yet, so it would be great to get a head start!
I just want to say I love these CCA videos. I'm usually unfairly cautious towards non-Hank/John presenters, but Phil is great.
Did I seriously just watch a class?!!?? This was soo entertaining
All I have to say is that you guys are f***ing awesome for posting all this incredible info in an easy to digest format for everyone!!! keep it up you guys rock.
soo much of your explanations about orbits could have used simple graphics imo. Seriously I don't think I could've followed without ksp.
I love that the one source you quote within the video is Douglas Adams. I get most of my scientific understandings from his writings too.
Ironically enough, I'm supposed to be writing a book report on Hitchhiker's Guide to the Galaxy right now.
Wow, this is the third time someone has explained this to me in less than 12 hours! First my physics teacher, then Randall Munroe in What if, which I was reading during my lunch break and now Phil... I'm sure not going to forget this any time soon : )
This video should be included in KSP.
Crash Course and Bad Astronomer mash up is the best idea ever, thanks so much for these videos.
I want the Enterprise to the left of the screen!
Where did you guys get it?
Enterprise from original series is better.
It's a Lego set. Go check it out :)
Great job! I will be using this soon under the gravity of the requirements as an instructor.
How about Crash Course Engineering (Mech,Electrical, Aero etc)?
those are pretty horrendously open fields of study that cover applied science in general
Jacob Shepley Not per se...
mechanical engineering is all about loads on structures. That and temperature. So a quick video describing how maximum loads are calculated would be nice.
Phyyyyyyyyyyyyyyssssssssssssssiiiiiiiiiiiics
i just realized a lot of the books in his table are his original works!!
here's a silly question. what is the escape velocity of the universe :)
where would you be escaping to?
As they always say in the science class, "no question is silly".
The escape velocity of universe depends on which direction you want to escape and what gravitational force is in your way.
If earth is the only object then your escape velocity is more than 11km/s and if there are more planets then you calculate the gravitational force according to the angle of the gravitational force minus the gravitational force of the planets ahead of you (which are pulling you in) according to their angle compared to your position.
there's no length, breadth, height, or time, or anything outside the universe, so yea...and the universe is expanding at pretty darn fast rate..theories say that going to the edge of the universe doesn't really take you to the end, in fact, if you keep going, you'll reach where you've started. kinda like going around the earth..
True, but I'm talking about normal conduction, which is universe is not moving or expanding and all the mass in the universe does not change or move.
Same calculation as when we calculated the force at which two or multiple protons place on one another.
In physics class when we calculate two trains moving towards each other, we are not considering the air resistance, wind speed, and friction. It makes the calculation hard and also discourages people from understanding the basic concept.
I don't think it's possible to calculate the escape velocity of the universe because we do not know its exact mass. We can estimate the mass of observable universe, but that's just the portion of space 13.8 light years in all directions from Earth, and there is probably more stuff beyond that.
This man is brilliant...
How do Star Wars characters always have seemingly normal gravity in spaceships?
I've yet to say this but i feel that i must by now. I love Crash Course and triple love Astronomy courses in it. Great job over all!
What would happen if objects gravity didn't extend out into the universe forever like they do now? Would anything change would we notice?
Depends on how the gravity dissipates.
If all of the universe had gravity we would crash into other planets duh
it's nice that you take your time to teach us all this. I guess that's partly why I like CrashCourse. Thank you so much
Phil!
Probably a silly question, but Planet Earth has more mass than the moon, so why does it not pull it into itself or does the Earths circular velocity throw it out? I can't think of another way to describe it.
well, the moon was formed after the earth collided with an object of roughly the same format. Maybe the millions of small particles (which later formed the moon) were blown into space, and were constantly falling (on 4:20 phil explains that)
Arnold Robert Lee The Moon is orbiting the Earth. Just like the Earth is orbiting the sun. So the reason the moon doesn't crash into the Earth is the same reason the Earth does not crash into the sun.
Arnold Robert Lee The moon doesn't crash into earth because the gravity of earth and the gravity of the sun mame the moon stay in the middle
For anything to fall down to earth (assuming the earth is motionless), all of its momentum (motion) has to be toward the earth. Consider the example of the ball. If you drop a ball from a height, all of its motion is in the downward direction (toward the earth). But if you give it a sideways push, it will still fall down but will land in a different spot because its motion is now in two directions: one is vertically downward toward the earth, the other is sideways, away from the earth. It just so happens that in this case, the downward motion is more powerful than the sideways motion. Hence the downward motion eventually wins and the ball hits the earth. However, if you give it enough sideways motion, the two motions will balance each other and the ball will get stuck. Its downward motion tries to bring it toward the earth but its sideways motion tries to take it away from the earth. And since the two are equal, the ball ends up doing neither. In other words, its distance from the earth doesn't change, which happens to be the definition of a circular orbit. I hope this helps. Btw things are a bit more complicated in reality because there are many more forces involved but this is essentially what happens. Hope this helps.
This is honestly the most mild and reasonable comments section on RUclips, the questions are reasonable, the arguments are sound, and for a science video there was no mention of religion or your own personal beliefs. (From what I've seen)
THESE VIDEOS ARE FUCKIN AWESOME!!!!
Best episode yet. Way to take a potentially complicated subject and make it very understandable.
I knew all this thanks to KSP and Scott Manley.
Hen Barrison n
I love this series. This is probably the best video yet.
Thank God there is CrashCourse
Wonderful! Again I have learnt something new and have had my memory refreshed!
Can you start:
Crash Course: Mathematics.
This will get tons of views.
Very attractive presentation here dealing with such weighty matters must have been a massive task.
Reading these comments makes me feel like I'm on the smart side of youtube. I've come along way from leeroy jenkins and the emo kid song.
Emo kid song?
I wish i had teachers like you back in high school.Awesome videos,awesome explanation neat and well structured .
Thank you.
I don't want that rock to escape:(
How dare you tell that rock what to do! Rocks have rights now! how don't you know this! have you been living under a ROCK!
I'm so sorry.
lol
Finally a proper explanation in the difference between mass and weight, THANK YOU
The escape velocity of what is 11 km/s? You're saying that a marshmallow and a sport stadium would need to reach the same velocity to escape Earth's gravity? I guess it has to do with the acceleration due to gravity. Never thought that the escape velocity would be the same for all masses ("escape acceleration" would be different though I do believe).
yeah, but the force to be exerted on the stadium would have to be a lots greater than the marshmallow
Yes! But see, as he described with regards to mass, it would take a LOT more energy to get a stadium collectively up to 11 km/s than a marshmallow up to 11 km/s.
Think about it this way: Voltron rockets off of Earth to its escape velocity of 11 km/s. Then, Voltron stops accelerating. At this state, the Cats-Bot is shooting away from the Earth without needing to speed up any more.
Then, Voltron separates. What speed is each of the five wildcats traveling at? That's right, they're each still traveling at 11 km/s away from Earth! The speed of an object is not the same as the energy put into it. The speed is related to the energy put into an object, as well as the mass of it.
P.S. BY THE WAY, Earth has an atmosphere. Even though you can build a marshmallow shooter that can pop out marshmallows at 11km/s, the marshmallow slows down due to air resistance far before it can escape the atmosphere. And shooting the marshmallow away from the Earth at a higher speed so that it would slow down to 11km/s when it reaches the edge of the atmosphere...would vaporize the marshmallow before it even got there. :(
This is for the same reason that if you drop two things of different masses they fall at the same rate.
They are following tandex lines?
Nick V the acceleration a mass would need to experience so that it had enough energy to escape Earth.
This is where things get confusing for me. I just don't understand mass and velocity. But still good to learn about it!! Another great video in this series!
SPOILER ALERT
Gravity isn't a force. It's all about curves ;)
EDIT:
Sorry guys, a lot of what you deliver is great and of a high quality standard, but this was just poor. I'm sure this video was aimed for a particular audience but you could at least mention that the best theory of gravity we have (Einsteins Relativity no less) demonstrates that Gravity isn't a force and that its really about the curving of what can be thought of as a 4D mathematical space and then reassure viewers to just think of it as a force for the sake of this video (you know, to keep things simple). When you mentioned that gravity warps the space around it, close, but that would be that mass warps spacetime (relativity again).
For those interested to know, gravity is NOT a force and really everything just moves in straight line vectors within the curvature of spacetime - spacetime being curved by MASS. Gravity doesn't bend light, mass bends spacetime and photons still travel in straight lines within a curved space (not light travelling in curves in a flat space).
Also, please excuse my avatar, I am a liberal and believe in peoples right to choose. Although I don't partake as much as I once did, it was blazing that got me fascinated and literally opened my mind to theoretical physics... dude.
Good god these are awesome. You are literally the only person on RUclips I can watch and listen to on these subjects without losing interest.
BUT WHAT CAUSES GRAVITYYYYY
The starting music of this Crash Course is by far my favorite
A Zillion light years away is older than the universe, so the earth's gravity wouldn't have reached there yet. :P
You're right, the "Speed of Gravity" must = c. It's almost proven, all we have to do is find the Graviton...
Joe Seph Well if that wasn't the case then you could use gravity to send information faster than light.
docopoper Well, probably? But why would we need FTL communications before some kind of FTL or Near-FTL form of propulsion? I guess it would fix the problem of Time Delay for a while, but it isn't that.. well, useful
A zillion light years is an distance, not a period of time. You are confusing it with looking back in time when observing a star that is a certain amount of light years away.
How many zeroes are in a zillion?
everything i learned about science at school this year in one video ! wow
Phil, you should have dressed as a princess yourself =(
Nice video though ;D
Best quote ever, loved all of those books :)
So long and thanks for all the fish.
Wow, I didn't find anything to nitpick this time. Everything was really carefully phrased. Actually, it almost sounded a bit forced ... hey, that was a joke! It was a joke, ok?
I didn't think it was that great.
electrocat1 I'm not keeping _you_ from nitpicking if you found loads of stuff.
Maybe a bit forced, but he's dynamic and attractive.
Free falling in space. That is a great explanation. I liked this video a lot!
wait we live on a planet, i thought it was the earth?
Gunflower, Earth is a planet! So are Mercury, Venus, Mars, Jupiter, Saturn, Uranus and Neptune, as well as thousands of similar bodies orbiting other stars
+The Utopiano Utopioan
I think it was a joke. Hard to tell online tho :)
We live in a society
No!!! We live on land. God why are these people so stupid?
I'm the owner of the profiles son and we home school. These videos are the best! I love these.Every time my mom says to watch a video on something I ask for a crash course vid! Bye!!
I hope you kiss him goodbye first because it ain't coming back
If only I had came across this series during high school my Physics scores would have been so good.
GRAVITY, DONT MEAN TOO MUCH TO ME
OMG YESSS
Gravity, the one force we find easiest to describe, but hardest to understand. Good introduction, without all the fun/scary math of orbital mechanics
"What goes up, must come down"
*NOBEL PRIZE AWARD*
No matter how many times I hear a science educator explain gravity, it still makes me giddy thinking about how people listening/watching will have their minds blown.
FUCK, I JUST REALISED
SPACE IS CALLED SPACE BECAUSE ITS EMPTY SPACE
WHY DIDN'T THEY TEACH THAT SHIT IN SCHOOL ARRRRRRRRRGH
FUCK MY LIFE UGGGGGGGGGGGGGGGGH
Same XD
Space isn't empty at all... Like at not even close to being empty, lmao
I have a astronomy test tomorrow, I haven’t studied. I’m hoping doing these crash courses help me at least get a base
i enjoyed this video and the graphics really helped me. more graphics the better. i understand the gravity weakness inverse ratio better than before due to the graphic. Thanks.
Thank you for a great explanation. It helps me understand more about gravity.
I wish you make a video about vectors in one dimension and then two dimension.
Once again, thank you for a great lesson.
Best Video yet in this course
just starting to view this. May I say that this is awesome? Thanks!
Wow this was mind boggling. I've watched this 5 times back to back.
Next on CC Astronomy ...Meteor showers!!! Yeah? Can we get that maybe?
Next after Tides that is. That should be a good episode :) This series is awesome, I love it!
Will you also be talking about how swing-by maneuvres work? I think I have figured it out (gravitation is acceleration; and that's speed change over time, not over distance; so you get accelerated more while flying to whatever body is used for the maneuvre than you get decelerated while flying back away from it) but it would still be very interesting to see that confirmed (or corrected!) in more depth and detail =) And since with deep-space exploration becoming bigger a thing, paired up with faster and faster computation (thus allowing more and more complex flight paths), swing-by maneuvres are bound to become even more and more important (well, until we get warp drive or something), I guess this topic might interest many viewers!
Phil, you always make this stuff so interesting. Great stuff.
I love this Crash Course series. So informative...
This video really helped me. Thank you very much!
What a great weight loss strategy!
Make videos forever pls. Love these
I’m mad because this video is too informative I can go on and on writing notes on this video w vid thanks sir your an great teacher thanks for the help
yay! you used one of my favorite Douglas Adams quote for describing orbits!