Calculate the Current Through a Resistor

This tool calculates the current (I) in Amperes. Enter the values of

  • Resistance in Ohm
  • Voltage in Volt

Formula

I = V/R

This is also known as Ohm’s law which states that the current through a conductor (I) with a constant resistance (R) between two points is directly proportional to the voltage (V) across the two points.

Ohm’s Law is the cornerstone of electrical circuits, explaining the relationship between voltage (V), current (I), and resistance (R). It’s a simple yet powerful formula that helps in designing, troubleshooting, and understanding electrical circuits.

Example Calculation

For a voltage value of 5 Volt and resistor value of 2 ohm, the current through the resistor is 2.5 Amperes or Amps.

Real-World Applications of Ohm’s Law

  1. Home Electrical Circuits: Ohm’s Law is used to design safe home electrical systems. For instance, electricians calculate the current that will flow through appliances to ensure the wiring can handle the load without overheating.
  2. Device Troubleshooting: Technicians use Ohm’s Law to troubleshoot electronics. If a device isn’t functioning properly, measuring the voltage and current can help diagnose faulty components.
  3. Battery Performance: When designing batteries, engineers use Ohm’s Law to calculate the voltage needed to power a device without overloading it.

Important Considerations:

  • If there are multiple resistors in the circuit, calculate the total resistance based on their configuration (series or parallel).
  • The power dissipated by the resistor can also be calculated using the formula P = I2 × RP , where P is power in watts (W).