If a hole is dug to the center of earth and a ball is dropped in it, the ball will:

Explanation

When a ball is dropped into a hole dug to the center of the earth, it will experience a force due to gravity that is proportional to its distance from the center of the earth. This means that the force is always directed towards the center of the earth. As the ball falls, the force of gravity will decrease until it reaches zero at the center of the earth. At this point, the ball will have reached its maximum velocity. However, the ball will not stop at the center of the earth. Instead, it will continue to move due to its inertia. As the ball moves past the center of the earth, the force of gravity will start to increase again, pulling the ball back towards the center. This will cause the ball to slow down until it comes to a stop at the other end of the hole. The ball will then start to fall back towards the center again. This process will repeat itself, causing the ball to oscillate back and forth through the hole.