⚡ Ohm's Law

Understanding Voltage, Current, and Resistance

Theory & Formula

Ohm's Law states that the electric current flowing through a conductor is directly proportional to the voltage applied across it and inversely proportional to its resistance, provided the temperature remains constant.

Primary Formula:

V = I × R
Where:
• V = Voltage (Volts)
• I = Current (Amperes)
• R = Resistance (Ohms)

Rearranged Formulas:

I = V ÷ R
R = V ÷ I

Key Relationships

Quantity Symbol Unit
Voltage V Volt (V)
Current I Ampere (A)
Resistance R Ohm (Ω)
💡 Remember: Increase voltage → Current increases. Increase resistance → Current decreases.

Ohm's Law Triangle

V I R

How to use: Cover the unknown quantity to find the correct formula

Calculator

volts
amperes
ohms
📝 How to use: Enter any two values and click Calculate to find the third value.