How Ohm’s law works
Voltage pushes current through a resistor. At a fixed resistance, doubling the voltage doubles the current. At a fixed voltage, doubling the resistance halves the current.
Choose any two known values to solve the other two. This example uses a single ideal resistor and nonnegative DC values. Current follows the probe arrow from the positive source terminal through R1; power is the energy dissipated as heat per second.
Edit V1 or R1 directly on the canvas, or choose Try in CircuitSim to simulate your values. To explore two resistors, open the voltage divider calculator.