00:02
In this case, we know that the velocity of an experimental space probe fired from the earth has a magnitude of 32 .5 times 10 to the third kilometers per hour, or 32 .5 megameters per hour, i guess you call it.
00:24
At point a, and we wanted to determine the speed at point b.
00:27
So we're giving a little diagram here at point a it's 4 ,300 kilometers above the earth, and at point b, it's 12 ,700 kilometers above the earth.
00:38
So here we have a and b.
00:41
And then the radius from the center of the earth, we need to tack on the radius of the earth to these heights.
00:48
So in the energy at a, we can, we need to use our regular form of kinetic energy.
00:58
Here and not because we don't have a circuit orbit.
01:02
So we just, we're given the velocity there.
01:05
So that's one half m v .a squared and then the potential energy...