RedCrab Math Tutorial

Electrical power

Electrical power in a circuit is the energy that is absorbed or generated in the circuit. The symbol for electric power is P.

Definition of Power

The electrical power is calculated from the voltage multiplied by the current. The unit of measurement of electrical power is the Watt (W).
The dependency can be defined as:
By definition, the power P = 1 W when the voltage U = 1 V and the current = 1 A.
With Ohm's law (U = I · R), the formula for the electric power can be changed as follows:


Resistor and Conductance
Ohm's Law
Specific Resistivity and Conductance
Resistors in Series
Resistors in Parallel
Wire Voltage Loss
Electrical Power

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