Question

Scientists and engineers are testing three different satellites orbiting Earth. The scientists are able to use sensors to determine the gravitational force experienced by each satellite. Some of the data from each of the orbiting satellites is shown in the table below.

Satellite Distance
from Earth
(km) Mass
(kg) Gravitational
Force
(N)
X 36,000 400 120
Y 36,000 1,200 360
Z 36,000 900 270

Which statement best summarizes the information given?
A.
The satellite with the least amount of mass is able to exert greater gravitational force on Earth than the others.
B.
The gravitational force on the satellite depends only on the distance from Earth at which it is traveling.
C.
The gravitational force exerted by Earth on the satellite depends on the satellite's mass.
D.
The gravitational force exerted by Earth changes the mass of each of the satellites.

Answer 1

C.

For all three satellites the distance from Earth is the same (36,000 km), and the measured force scales directly with satellite mass (400 kg → 120 N, 1,200 kg → 360 N, 900 kg → 270 N). This matches Newton’s law of gravitation F = G Mearth m / r^2, so for a fixed r the gravitational force depends on the satellite’s mass.