What is the force of gravity acting on a 2000-kg spacecraft when it orbits two Earth radii from the Earth's center (that is a distance r=6380 km above the Earth's Surface. The mass of the Earth is 5.98 x 1024 kg.

F = 4.816 * 10 ⁻¹⁰ N

Explanation:

mass of earth M = 5.98 * 10²⁴ m, mass of the spacecraft m = 2000 kg,

distance between the spacecraft and earth's center

r = 6380 * 10³m + 6.38 * 10⁶ m = 4.07 * 10¹³ m

Formula for force of gravity is

F = G M m / r²

F = 6.67 * 10⁻¹¹ Nm² / kg² * 5.98 * 10²⁴kg * 2000 kg / (4.07 * 10¹³ m) ²

F = 4.816 * 10 ⁻¹⁰ N