Ohm's Law and Power Calculator
An online calculator to calculate the current passing through a resistor using Ohm's law and the power dissipated in a resistor given the voltage across the resistor.
This calculator also calculates the voltage and current through a resistor given the power dissipated by this resistor.
Ohm's law expresses the relationship between the current I passing through a resistor and the voltage V across that resistor of resistsnce R as follows:
V = R I , I = V / R or R = V / I
The rate at which heat is dissipated in a resistor is called power P and is given in terms of current I and voltage V by:
P = V I
Using Ohm's law above, we can rewrite the power P as
P = R I 2 , P = V 2 / R
1 - Ohm's law and Power Calculator Given Voltage and Resistance
Enter the resistance in Ohms and the voltage in volts as positive real numbers and press "Calculate Current and Power".
2 - Ohm's law and Power Calculator Given Power and Resistance
Enter the power in Watts and the resistance in Ohms and press "Calculate Voltage and Current".
More References and LinksOhm's law with Examples
Free SAT II Physics Practice Solutions on
DC Electric Circuits