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watt

Meaning: a standard unit of power | abbreviation: W

For example:

  • We replaced all of our 100-watt lightbulbs with 60-watt bulbs.

  • On your utility bill, electricity usage is usually measured in kilowatts.

Origin: James Watt (1736-1819) was a Scottish engineer and inventor who was interested in improving the efficiency of steam engines. He invented the separate condenser, which condensed steam without cooling the internal walls of the piston and cylinder. He also invented a rotary motion powered steam-engine, which replaced the up and down pumping action with a forward and backward motion. These two improvements to the steam-engine made it more energy efficient. The standard unit of power was named after Watt in honour of his inventions.

Quick Quiz:

Which is usually measured in watts?

a. lightbulb power

b. car speed

c. lightning

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Contributor: Tara Benwell