Question

It took the Space Shuttle Orbiter about 90 min to complete one trip around the Earth. Estimate the spacecraft’s orbital velocity in units of mph. Make the approximation that the altitude of the spacecraft (approximately 125 mi) is small when compared to the radius of the Earth (approximately 3950 mi).

Answer 1

The approximation made is that the altitude of the spacecraft is small when compared to the earth’s radius. This means that the path travelled by the spacecraft is equal to the earth’s radius 3950 mil. The time taken to complete 3950 mil time taken is 90 min. Hence the distance travelled in 1 hr is

 

(9550 mi) × {1 h/(90/60) h} = 2633.3 mi

 

Therefore the orbital velocity is 2633.3 mph.

Therefore the orbital velocity is 2633.3 mph.