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Unit of work

The SI unit of work is the joule $$(\text{J})$$. One joule is the work done when a force of $$1\text{ N}$$ displaces an object by a distance of $$1\text{ m}$$ in the direction of the force.

In SI base units, the joule can be expressed as $$\text{N m}$$. That is also the unit of the moment (or turning effect) of a force but moments and and work are very different and should not be confused.

Work done is a scalar quantity and a moment is a vector quantity. Work is always expressed in $$\text{J}$$ and moments in $$\text{N m}$$.

The quantities weight and work both have the same symbol ($$W$$), so it is important not to confuse the two in equations.

The joule is named after the scientist James Prescott Joule. Joule spent a lot of time working on work. He also had an impressive beard.
The joule is named after the scientist James Prescott Joule. Joule spent a lot of time working on work. He also had an impressive beard.