Discuss the below:
Q: The gravitational force on a body located a distance R from the center of a uniform spherical mass is due solely to the mass lying at distance r
Use the above result to show that if you drill a hole through the earth and then fall in, you will execute simple harmonic motion about the earth's center. Find the time it takes you to return to your point of departure and show that this is the time needed for a satellite to circle the earth in low orbit with r approximately equaling R(earth). In deriving this result, you need to treat the earth as a uniformly dense sphere, and you must neglect all friction and any effects due to the earth's rotation.