Question

A generator produces 60 000 J of electric energy every minute. How many watts does it produce?

Answer 1

`1000\; {\rm W}`.

Step-by-step explanation:

Joule is a unit for work, while watt is a unit for power- the rate at which work is being done. Divide work by time to find power.

By definition, one watt is equivalent to one joule-per-second. In other words:
`1\; {\rm W} = 1\; {\rm J \cdot s^(-1)}`. Note that the unit of time in this question is "minute", not second.

Apply unit conversion and ensure that the unit of time is "second":

`\begin{aligned} 1\; \text{minute} &= 1\; \text{minute} * \frac{60\; {\rm s}}{1\; \text{minute}} = 60\; {\rm s}\end{aligned}`.

The power of this generator would thus be:

`\begin{aligned} \text{power} &= \frac{\text{work}}{\text{time}} \\ &= \frac{60\, 000\; {\rm J}}{60\; {\rm s}} \\ &= 1\, 000\; {\rm W} \end{aligned}`.