What does a joule measure?

A joule is defined as the unit of energy within the International System of Units (SI). It quantifies the amount of work done when a force of one newton is applied over a distance of one meter. This fundamental relationship links energy directly to both work and heat transfer.

Understanding this is crucial, as energy is a core principle in various fields, including physics and engineering. The joule helps to provide a standard measurement for energy conversion and usage in both theoretical and practical applications.

Other options, such as distance, force, and power, measure different physical quantities, but the joule specifically relates to energy, making it the correct choice for this question.