How work (= energy) is spread over time

Power is the rate at which mechanical work is done. The more power we use, the faster we can do a given amount of work.

Power is work divided by time,

or the amount of change in energy divided by the change in time:

The concept of power allows us to compare the ability of systems to accomplish a certain energy change or a certain amount of physical work.

In this brief section, we'll define power, talk about its units and do a couple of sample calculations.

Power is the rate at which mechanical work is done.

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