Which unit is commonly used to measure energy transfer?

The Joule (J) is the standard unit for measuring energy transfer in the International System of Units (SI). It quantifies the amount of energy expended when a force of one newton is applied over a distance of one meter or when one coulomb of electric charge moves through an electric potential difference of one volt. This makes the Joule a fundamental unit in various fields including physics, engineering, and chemistry, allowing for a consistent way to express energy in different contexts, such as kinetic energy, potential energy, thermal energy, and electrical energy.

The other units listed serve different purposes. The Watt measures power, which is the rate at which energy is transferred. Voltage is measured in Volts, which indicates electric potential, while Ohms measure electrical resistance. Therefore, while all these units relate to energy and electricity, Joules specifically measure the transfer of energy itself.