The diagram shows a simple pendulum.

Question

Neglecting friction, what happens to the total mechanical energy as the pendulum swings from position A to position B?

a
It is not conserved.
b
It decreases.
c
It remains the same.
d
It increases.

Answer 1

In the case of a simple pendulum, if we neglect friction and air resistance, the total mechanical energy of the system is conserved. The total mechanical energy is the sum of potential energy and kinetic energy. As the pendulum swings from position A (the highest point) to position B (the lowest point), potential energy is converted into kinetic energy, but the total mechanical energy remains constant.

Therefore, the correct answer is:

c) It remains the same.