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Physics vocabulary · Electricity and Magnetism

Ohm's law

Meaning in physics, with examples

nounCore term

In physics, Ohm's law means: The rule that the current through a metal conductor is directly proportional to the voltage across it, as long as its temperature stays the same. It is usually written V = IR.

In Turkish: Ohm yasası, Ohm kanunu

How it is used

One of the first equations students use in circuits. Components that follow it are called ohmic, and their current-voltage graph is a straight line through the origin. Filament lamps and diodes are non-ohmic. Say 'using Ohm's law' or 'by Ohm's law'.

Example sentences

  1. Using Ohm's law, a 12 V supply across a 4 Ω resistor gives a current of 3 A.

  2. The diode does not obey Ohm's law, so its graph is curved.

Common collocations

  • obey Ohm's law
  • using Ohm's law
  • ohmic conductor
  • non-ohmic component
  • resistanceHow strongly a component or material opposes the flow of electric current. It equals voltage divided by current and is measured in ohms (Ω).
  • 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.
  • circuitA closed path through which electric current can flow, made of a power source, wires and components such as lamps, resistors and switches.
  • directly proportionalDescribes two quantities that change at the same rate, so that if one doubles the other doubles too. Their graph is a straight line through the origin.

This word in other fields

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

More terms: Electricity and Magnetism

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