What is the formula that describes power dissipated by a resistor?

The formula that describes power dissipated by a resistor encompasses several equivalent expressions for calculating power, which can be understood through Ohm's Law and the relationships between voltage (V), current (I), resistance (R), and power (P).

Power, in the context of electrical systems, is defined as the rate at which energy is used or converted, and it can be expressed in different ways depending on the known variables:

1. The direct relationship through current and voltage is represented by the formula ( P = IV ), where power (P) is the product of current (I) flowing through the resistor and the voltage (V) across it.

2. When using Ohm's Law, where ( V = IR ), we can substitute this expression into the power formula to derive ( P = I( IR ) = I²R ), showing that power can also be expressed as the product of the square of the current and the resistance.

3. Another variation arises if we manipulate Ohm's Law differently. If we solve for current in terms of voltage and resistance, ( I = V/R ), and substitute into ( P = IV ), we can derive ( P = V(V/R) = V²/R ), allowing