Energy is measured in which unit?

The measurement of energy in physics is defined in Joules. This unit quantifies the amount of energy transferred or converted when a force is applied over a distance. In the context of laser therapy and other applications, understanding energy in Joules is crucial because it provides a clear measurement of the energy output of the device being used and the energy absorbed by the tissues.

Other units listed—Watts, Volts, and Amperes—serve different purposes in the measurement of electricity and power. Watts are a measure of power, which is the rate at which energy is consumed or produced. Volts measure electric potential or voltage, which indicates the potential difference that drives electric current through a circuit. Amperes measure the flow of electric current. While all these units relate to electricity and energy in some capacity, Joules are specifically designated for measuring energy itself, making it the correct choice for the question posed.