Ohm's Law

Currents, voltage and resistance

What Is Ohm's Law?

Ohm's Law represents the relationship between voltage (V) and current (A).
Ohm's Law states that the voltage across a circuit is proportional to the current through it. The constant would be the resistance (Ω/R).


Current electricity is defined as the flow of electrically charged particles. This can be divided into two types of currents:

  • DC (Direct current)
    Direct current flows in one direction.
    DC is available in batteries
  • AC (Alternating current)
    Alternating current periodically reverses the direction in which it flows.
    AC is available from wall outlets


Voltage is the potential difference in a circuit. Voltage can be stored energy, which in order to use, must be connected in a circuit.
An example of a source of voltage would be a common household item, a battery.
This can power many things such as a TV remote, a flashlight or a radio.

A Video To Explain Ohm's Law Even Further

MAKE presents: Ohm's Law