Practice question · True or false
The minus sign in Faraday’s law is required by conservation of energy.
Hints
- Imagine the sign were positive and follow the consequences.
- A self-reinforcing induced current would create energy from nothing.
Show the answer
True
Why
True, with the opposite sign, an induced current would strengthen the change that produced it, amplifying without limit and generating energy from nothing. Lenz’s law is energy conservation expressed as a direction.
Practise Electromagnetic Induction
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