Consider a tunnel excavated along a diameter of the earth. A particle is released from a point at a distance h directly above the tunnel. As viewed from the earth, the motion of the particle is

Step-by-step solution

When the particle is released from a height h directly above the tunnel, it falls towards the center of the earth due to gravity. Assuming the earth is non-rotating, the initial velocity is zero, and the gravitational force is purely radial. Thus, the particle moves along a straight line passing through the center of the earth. For r > R (outside the earth), the gravitational force is F = - GMm r^2 . For r Since the force is always directed towards the mean position (center of the earth) and the system is conservat