What is the unit of work in the SI system?

The unit of work in the International System of Units (SI) is the joule. Work is defined as the energy transferred when a force is applied over a distance. In physics, when a force is exerted in the direction of movement, the work done is calculated as the product of the force and the distance moved in the direction of the force.

One joule is equivalent to the work done when a force of one newton is applied over a distance of one meter. This relationship establishes the connection between the unit of work (joule), the unit of force (newton), and the unit of distance (meter).

The other units listed in the choices have different definitions and applications:

• The newton measures force, not work.

• The pascal is a unit of pressure, which is force per unit area.

• The watt is a unit of power, defined as one joule of work done per second.

Understanding that joule specifically quantifies work allows for clarity in calculations and applications across various fields of physics and engineering.