Question

Consider a frictionless tunnerl through the center of the earth. With what speed would an object pass frm one side of the earth to the other?

Answer 1

When an object dropped from one end of the tunnel then at center of the earth the object will make simple harmonic oscillations means the object is in simple harmonic motion about the center of the earth. So the object never comes to another end hence we cant calculate the speed at other end.