Author Question: What holds a circularly-moving satellite in orbit while the force of gravity pulls downward on it? ... (Read 79 times)

Frost2351 · **on:** Jul 29, 2018

What holds a circularly-moving satellite in orbit while the force of gravity pulls downward on it?

What will be an ideal response?

Question 2

What is the period (in hours) of a satellite circling Mars 100 km above the planet's surface? The mass of Mars is 6.42 1023 kg, its radius is 3.40 106 m, and G = 6.67 10-11 N m2/kg2.

A) 1.75 h
B) 1.25 h
C) 1.15 h
D) 1.00 h
E) 1.45 h

Juro · **Reply #1 on:** Jul 29, 2018

Answer to Question 1

Answer: Nothing holds the satellite in orbit. It remains in orbit because the force of gravity pulls perpendicular to its motion, just as the speed of a bowling ball on a lane isn't changed by gravity. With no component of force in the direction of motion, no change in speed occurs. Only a change in direction occurs. The satellite has enough tangential speed to simply match Earth's curvature below.

Answer to Question 2

A