Category:Joule's Law & Resistive Power

Power, the rate of doing work, is equal to the voltage multiplied by current.

The Unit of electrical Power is called the watt. One watt is equal to 1 volt multiplied by 1 ampere. The Power (P), 1 watt is also one joule per second or the Energy (W) per unit of Time (s). The JouIe is the Energy Dissipated as Heat.

P (watts) = V(volts) x I (amperes)

By substituting the Ohm’s Law equivalent for V and I, the new formulas are obtained as shown below.

If you know the voltage and the resistance:

P (watts) =

If you know the resistance and the current:

P(watts)=R(ohms)x I²(amperes)

P=RxI²

In a Resistance, Electrical Power is turned into heat. The higher the power, the faster the heat is generated. Cool them if needed!!! Joule’s Law is shown below.

W (joules)=R(ohms) x I²(amperes) x T (seconds)

W (joules) = P (watts) x T (seconds)

W (Energy) = R x I² x T