Watt (W)

Definition

The watt (W) is the SI unit of power, defined as one joule per second. It quantifies the rate of energy transfer or conversion.

History

• 1782: James Watt developed the steam engine, leading to the unit's naming.
• 1882: The term "watt" was adopted at the International Electrical Exhibition in Paris.
• 1960: The watt became an official SI unit during the 11th General Conference on Weights and Measures.

Uses

Watt is used to measure electrical power, mechanical power, and thermal power. Common uses include:

• Electrical appliances (light bulbs, heaters)
• Industrial machinery
• Audio equipment (amplifier power ratings)

Conversions

• 1 W = 1 J/s (joule per second)
• 1 kW = 1,000 W
• 1 MW = 1,000,000 W

Fun Facts

• A common misconception is that "watt" refers to the total energy consumed; it actually measures power, or energy per unit time.
• The watt-hour (Wh) is often used to express energy consumption, especially in household electricity bills.