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A watt measures power. What is one watt equal to?

One joule per second: power is how fast energy is used or delivered.

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  1. One joule per hour
  2. One newton per meter
  3. One joule per second ✔

Why: Power is the rate of doing work. A 100 W bulb uses 100 joules every second. The watt hour is an amount of energy, not a power.

Huh, didn't know that: One horsepower is about 746 watts.

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Watt did the light bulb say to the switch? You turn me on.
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References

Answer: One joule per second. Power is the rate of doing work. A 100 W bulb uses 100 joules every second. The watt hour is an amount of energy, not a power.

  1. OpenStax University Physics Volume 1: 7.4 Power openstax.org/books/university-physics-volume-1/pages/7-4-power
    power is measured in units of joules per second, which has been given the SI name watts, abbreviation W
    Checked 2026-10-10.

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