Electric Power is the rate at which electrical energy is transferred by an electric circuit. It is measured in watts (W), which is equal to joules per second (J/s).
Power Dissipation is the rate at which electrical energy is converted into heat by an electrical device. It is also measured in watts (W).
P = VI
where:
P is the electric power in watts (W)
V is the voltage in volts (V)
I is the current in amperes (A)
Energy in a resistor is the electrical energy that is converted into heat by the resistor. The electrical energy that is converted into heat by a resistor is equal to the product of the current that flows through the resistor, the voltage drop across the resistor, and the time for which the current flows.
The formula for the energy in a resistor is:
E = I^2 R t
Where:
E is the energy in joules (J)
I is the current in amperes (A)
R is the resistance in ohms (Ω)
t is the time in seconds (s)
Joule’s Law states that the amount of heat generated in a conductor is proportional to the square of the current flowing through the conductor, the resistance of the conductor, and the time for which the current flows.
The formula for Joule’s Law is:
H = I^2 R t
Where:
H is the heat energy in joules (J)
I is the current in amperes (A)
R is the resistance in ohms (Ω)
t is the time in seconds (s)