How to Calculate Lenz Law
What is Lenz Law?
Lenz's law states that induced currents oppose the change causing them. It ensures energy conservation and determines the direction of induced effects.
Step-by-Step Guide
- 1Apply the right-hand rule with thumb opposite to flux change direction
- 2Fingers curl in direction of induced current
- 3Induced field opposes the original change
Worked Examples
Input
Increasing flux into coil (using right-hand rule)
Result
Induced current creates field opposing the increase
Lenz's law applies
Common Mistakes to Avoid
- ✕Assuming induced effects aid the cause (incorrect)
- ✕Confusing current direction with field direction
Frequently Asked Questions
Why does Lenz's law matter?
It ensures electromagnetic induction follows energy conservation; induced effects always oppose changes.
Is Lenz's law separate from Faraday's law?
No, the negative sign in Faraday's law IS Lenz's law; it's the same concept expressed mathematically.
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