00:01
For number 65, there's a satellite that's in a geosynchronous orbit above the earth.
00:08
So it always stays above the same spot.
00:10
And we're told the altitude of that, and we're told the radius of the earth.
00:14
So i can add those together, because here's the radius of the earth plus this altitude would be the radius of the orbit.
00:21
So this r is the radius of the orbit.
00:23
I'm getting it by just adding these two together.
00:26
So that's 4 .217 times 10 to the 7th meters.
00:33
And we're asked its speed.
00:35
Well, if i get at speed, the distance it goes is one time around every 24 hours.
00:41
So one time around is a circumference, 2 pi r.
00:47
And i know they are.
00:53
And the time to go around is one day.
00:56
So that's 24 hours...