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Physics vocabulary · Energy, Work and Momentum

Power

Meaning in physics, with examples

/ˈpaʊər/nounCore term

In physics, power means: The rate at which energy is transferred or work is done, in other words energy per second. It is measured in watts (W), where one watt is one joule per second.

In Turkish: güç

How it is used

Used in mechanics (the power of a motor), electricity (P = VI) and waves. Common phrases: power output, power input, rated power and power loss. Do not mix up power and energy: a kettle has a power of 2 kW, but the energy it uses depends on time.

Example sentences

  1. The motor lifts a 100 kg load by 3 m in 6 s, so its useful power output is about 500 W.

  2. Power is energy transferred per unit time, so a 60 W bulb transfers 60 joules every second.

Common collocations

  • power output
  • power input
  • rated power
  • power loss
  • generate power
  • energyThe ability of a system to do work or cause change. It comes in many forms, such as kinetic, potential, thermal and chemical, and it is measured in joules (J).
  • workThe energy transferred when a force moves an object through a distance in the direction of the force. It equals force times displacement and is measured in joules (J).
  • efficiencyThe fraction of the energy put into a device that comes out as useful energy. It is given as a decimal or a percentage and can never be more than 100%.
  • voltageThe energy transferred to or by each coulomb of charge between two points in a circuit, also called potential difference. It is measured in volts (V).
  • electric currentThe rate at which electric charge flows past a point in a circuit. It is measured in amperes (A), and one ampere is one coulomb of charge per second.

This word in other fields

The same English word can have a different meaning in another field:

More terms: Energy, Work and Momentum

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