Which formula correctly calculates power (mechanics)?

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Multiple Choice

Which formula correctly calculates power (mechanics)?

Power is how quickly work is done. Work is the energy transferred when a force moves an object a distance, and it is calculated as work = force × distance (in the direction of motion). Power, the rate of doing that work, is work divided by time: power = work / time. Using units, if work is in joules and time in seconds, power comes out in joules per second, or watts. Think of it this way: if you do the same amount of work faster, you’re delivering more power. For example, doing 10 joules of work in 2 seconds gives 5 watts of power (10 J ÷ 2 s = 5 W). The other ideas mix up what power measures: force × distance gives work, not power; time divided by work is the inverse of power; mass × acceleration gives force, not power.

Power is how quickly work is done. Work is the energy transferred when a force moves an object a distance, and it is calculated as work = force × distance (in the direction of motion). Power, the rate of doing that work, is work divided by time: power = work / time. Using units, if work is in joules and time in seconds, power comes out in joules per second, or watts.

Think of it this way: if you do the same amount of work faster, you’re delivering more power. For example, doing 10 joules of work in 2 seconds gives 5 watts of power (10 J ÷ 2 s = 5 W). The other ideas mix up what power measures: force × distance gives work, not power; time divided by work is the inverse of power; mass × acceleration gives force, not power.

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