Which statement about energy use is true when two bulbs, one 60 W and one 100 W, are used for the same amount of time?

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Multiple Choice

Which statement about energy use is true when two bulbs, one 60 W and one 100 W, are used for the same amount of time?

Energy used over a period equals power times time. If two bulbs run for the same amount of time, the one with the lower power rating uses less energy because it uses energy more slowly. A 60 W bulb delivers 60 joules every second, while a 100 W bulb delivers 100 joules every second; over the same duration the 60 W bulb accumulates less energy. For example, running for one hour gives 60 Wh for the 60 W bulb and 100 Wh for the 100 W bulb, so the 60 W bulb uses less energy. Voltage sets power in conjunction with current, but once you have the power ratings, the time-on determines total energy.

Energy used over a period equals power times time. If two bulbs run for the same amount of time, the one with the lower power rating uses less energy because it uses energy more slowly. A 60 W bulb delivers 60 joules every second, while a 100 W bulb delivers 100 joules every second; over the same duration the 60 W bulb accumulates less energy. For example, running for one hour gives 60 Wh for the 60 W bulb and 100 Wh for the 100 W bulb, so the 60 W bulb uses less energy. Voltage sets power in conjunction with current, but once you have the power ratings, the time-on determines total energy.

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