Question

Calculate the earth's gravity force on a 75 kg astronaut who is repairing the hubble space telescope 600 km above the earth's surface express your answer using two significant figures.

Answer 1

Given: Mass of the astronaut Ma = 75 Kg

Radius of the earth re = 6.38 x 10⁶ m

Altitude of the astronaut h = 600 Km = 600,000 m

Total radius will be r = 6.38 x 10⁶ m + 600,000 r = 6.98 x 10⁶ m

G = 6.67 x 10⁻¹¹ N.m²/Kg²

Mass of Earth Me = 5.98 x 10²⁴ Kg

Formula: F = GmeMa/re²

F = (6.67 X 10⁻¹¹ N.m²/Kg²)(5.98 X 10²⁴ Kg)(75 Kg)/(6.98 x 10⁶ m)²

F = 2.99 x 10¹⁶ N.m²/4.87 x 10¹³ m²

F = 613.96 N or around 615 N