Question

A polar satellite is launched at 850 km above Earth. Find its orbital speed. (7431 ms)​

Answer 1

Answer:

Anything in low earth orbit moves at about five miles per second, or an orbit every one and a half hours.

You can work out orbital speed at any altitude by calculating how fast you have to move that as you fall towards earth due to gravity, the earth’s surface is falling away at the same rate.

For LEO, you can use g = 9.8 m/s^2, same as on the surface. For much higher altitudes, you would need to compute acceleration due to gravity at that altitude.