Physics Formula
Ohm's Law Formula
Connects voltage, current, and electrical resistance.
Formula Summary
Ohm's Law
Connects voltage, current, and electrical resistance.
- Category
- Physics
- Equation
- V = I × R
- Calculator
- Use Ohm's Law Calculator →
Equation
V = I × R
Variables
- V = voltage
- I = current
- R = resistance
How to Use This Formula
- Identify the known values from the problem statement.
- Convert all values into compatible units.
- Substitute the values into the equation and calculate the result.
- Check that the final answer has the correct unit and meaning.
Explanation
Ohm's Law describes the relationship between voltage, current, and resistance in an electrical circuit. It shows how current changes when voltage or resistance changes.
Worked Example
A circuit with 12 volts and 4 ohms of resistance has a current of 12 ÷ 4 = 3 amperes.
Common Mistakes
- Mixing voltage, current, and resistance values.
- Using incorrect electrical units.
- Assuming resistance stays constant in every component.
Applications
- Designing and analyzing electrical circuits.
- Calculating current flow in electronics.
- Electrical laboratory experiments.