The diagram shows a swinging pendulum.

Which best explains what happens to the motion of the pendulum due to the law of conservation of energy?

A. The mechanical energy transforms to thermal energy as the pendulum slows and eventually stops moving.

B. The mechanical energy disappears as the pendulum slows and eventually stops moving.

C. The pendulum will continue moving at the same speed until someone stops it because energy cannot be destroyed.

D. The pendulum will slow down but will never stop moving because energy cannot be destroyed.

The motion of pendulum, the mechanical energy has been transferred to thermal energy. Thus, option A is correct.

The law of conservation of energy has been defined as the energy of the system in the reaction has been conserved in the product. It has been stated that the energy can neither be created nor  be destroyed.

The energy posed by the moving pendulum has been the kinetic energy. The energy posed by the pendulum at rest has been the potential energy.

The potential and kinetic energy of the system has been the mechanical energy.

The moving pendulum has been possessed with the thermal energy. There has been friction that results in the thermal energy of the system to be converted to mechanical energy.

Thus, in the motion of pendulum, the mechanical energy has been transferred to thermal energy. Thus, option A is correct.

Learn more about motion of pendulum, here:

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Explanation:

The law of conservation of energy states that the amount of energy is a constant, that is, it cannot be created or destroyed, it just can be transformed into different forms.

For example, in real life, a pendulum will stop moving eventually. But, why is the pendulum going to stop? Because, there's friction in that motion, which means that the energy that's being used, it's transforming into heat by friction. In terms of energy, that heat represents a subtractor of the movement.

So, the mechanical energy, which is kinetic and potenial, it's transforming to "thermal energy", making the pendulum to slow down, until stops.

Now, in a perfect environment (which doesn't exist), the pendulum would never stop, and there weren'n any heat, because there wouldn't be friction. But that's not the case here.

Therefore, the best answer is A.