Which statement defines power?

• A. The time rate of doing work
• B. The distance traveled in a given time
• C. The force applied during motion
• D. The total work performed

Answer: (A)

Power is the rate at which work is done or energy is transferred. It measures how quickly energy is used or moved. Power = work divided by time, so doing the same amount of work in less time increases power, while taking more time decreases it. The unit is the watt (one joule per second).

Distance traveled in a given time describes speed, not power. The force applied during motion relates to how much energy is transferred but, by itself, doesn’t specify how fast that transfer occurs. The total work performed tells you how much energy was transferred overall, not how quickly it happened. For example, lifting a 50 kg weight 1 meter in 0.5 seconds uses 490 J of work, but the power is 490 J / 0.5 s = 980 W; lifting it in 5 seconds uses the same work but only 98 W.