Understanding Gravity - AP Physics C: Electricity and Magnetism

Card 1 of 44

0
Didn't Know
Knew It
0
1 of 2019 left
Question

A spherical asteroid has a hole drilled through the center as diagrammed below:

Hole through planet

Refer to the diagram above. An object that is much smaller than the asteroid is released from rest at the surface of the asteroid, at point a. How do the velocity and acceleration of the object compare at point b at the surface, and point a, located at the center of the asteroid?

Tap to reveal answer

Answer

Because the gravitational force depends only on the mass beneath the object (which is the gravitational version of Gauss's Law for charge), the acceleration steadily decreases as the object falls, and drops to zero at the center. Nevertheless, the velocity keeps increasing as the object falls, it just does so more slowly.

← Didn't Know|Knew It →