Formula

V = I × R

Result

Voltage (V) = 12 V

Ohm's Law Triangle
Ohm's Law Triangle

V = I × R

Voltage vs Current

Example Calculations

Example 1

I = 2 A, R = 5 Ω

V = I × R = 2 × 5

V = 10 V

Example 2

V = 9 V, R = 3 Ω

I = V / R = 9 / 3

I = 3 A

Example 3

V = 12 V, I = 2 A

R = V / I = 12 / 2

R = 6 Ω

Understanding Ohm's Law

Ohm's Law describes the relationship between voltage (V), current (I), and resistance (R) in an electrical circuit. The law states that the current through a conductor between two points is directly proportional to the voltage across the two points, and inversely proportional to the resistance between them.

  1. Select the variable you want to calculate (V, I, or R)
  2. Enter the two known values in the input fields
  3. Select appropriate units for each value
  4. The calculator will automatically display the result
  5. Use the graph to visualize the relationship between voltage and current

  • Circuit Design: Determine appropriate resistor values for desired current
  • Troubleshooting: Identify issues in circuits by measuring voltage and current
  • Power Supplies: Calculate current draw for proper power supply selection
  • LED Circuits: Calculate required resistors for LEDs based on supply voltage