Question

A box is held at rest above the ground. Some time later, the box is released, and it falls towards the ground. Which statement below accurately describes what happens to the ball as it falls? A. The total mechanical energy of the ball increases, but its kinetic energy decreases. B. The total mechanical energy of the ball decreases, but its potential energy increases. C. The total mechanical energy of the ball remains the same, but its kinetic energy decreases. D. The total mechanical energy of the ball remains the same, but its potential energy decreases.

Answer 1

The total mechanical energy of the box remains constant as it falls, with its potential energy decreasing and converting into kinetic energy. The statement that accurately describes what happens to the box as it falls towards the ground is: D. The total mechanical energy of the ball remains the same, but its potential energy decreases.

Step-by-step explanation:

• As the box falls towards the ground, the correct answer is D. The total mechanical energy of the box remains the same, but its potential energy decreases.
• This is because, in the absence of air resistance or any other dissipative forces, the mechanical energy, which is the sum of kinetic and potential energies, is conserved according to the Law of Conservation of Mechanical Energy.
• When the box is initially at rest and held above the ground, it has maximum potential energy and zero kinetic energy. As it falls, its potential energy is converted into kinetic energy.
• However, the total mechanical energy of the system does not change, it simply transitions from one form to another. Therefore, as the box falls and gains speed, its kinetic energy increases while its potential energy decreases.