The power (the energy dissipation rate) of a resistor can be calculated using Ohm's Law and the formula for electrical power:
Power = Voltage x Current
Alternatively, using Ohm's Law (V = IR), the formula can be expressed as:
Power = I^2 x R
where:
Power is measured in watts (W)
Voltage is measured in volts (V)
Current is measured in amperes (A)
Resistance is measured in ohms (Ω)
This formula represents the amount of energy per unit of time that is dissipated by a resistor as heat. It is important to note that resistors have a power rating, which indicates the maximum amount of power they can safely dissipate without overheating or failing.