What is Power Dissipation with Regards to Resistors? The power that is dissipated by a resistor, or the equivalent resistance of a resistor network, can be calculated with the following equations:
Where P represents power, I represents current and V represents voltage. The first equation is derived from Joule's first law. Ohm's Law derives the other two from the first. All three equations are equivalent and can thus be written as:
If the power dissipated is more than a resistor can safely dissipate, the resistor may depart from its nominal resistance and can become damaged due to overheating. Extreme power dissipation can raise the temperature of a resistor to a point where it burns out; this can lead to a fire in adjacent materials and components. |
