- #1
- 4,807
- 32
HallsofIvy wrote in another thread:
Just yesterday I was asking myself that very same question. So thanks for giving such a nice an simple explanation.
I was also wondering why the atmosphere revolves with the earth; something you stated but didn't explained. Is it something that goes back to the time of the creation of the earth? Most unlikely imo. So what is the reason?
And why is there an atmosphere in the first place? I.e. why doesn't it just fall down on Earth like a decent piece of matter?
HallsofIvy said:What your friend meant by "because of the atmosphere" is that the atmosphere moves with the earth. You could not, as I have heard said, go up in a balloon and then wait while the Earth revolved under you! The balloon moves with the air which moves with the earth.
Without the atmosphere, the answer might be a little different. When you are standing on the surface of the earth, you are revolving with it: your eastward speed is exactly the same as the surface of the Earth (and so is the speed of the ball in your hand. As the ball moves upward, it retains that motion BUT, since the radius of the circle it is describing eastward is now longer, moving the same speed to the east results in a smaller angle: The ball would, in fact, fall slightly westward of you!
(That is a variation on "coriolis" force.)
Just yesterday I was asking myself that very same question. So thanks for giving such a nice an simple explanation.
I was also wondering why the atmosphere revolves with the earth; something you stated but didn't explained. Is it something that goes back to the time of the creation of the earth? Most unlikely imo. So what is the reason?
And why is there an atmosphere in the first place? I.e. why doesn't it just fall down on Earth like a decent piece of matter?