How is Lenz's law related to the law of conservation of energy?

The Russian Physicist Lenz inserted the "##-##" in the Faraday's Law. Without this sign the electromagnetic induction would produce infinite , breaking the principle of .

I'll show it with a simply paradox.

• Let us consider a metallic round spire with a variable magnetic flux.
• If the correct law were ##epsilon=(dPhi)/(dt)## the induced current would increase the magnetic flux ##Phi##.
• This would increase the induced currents, which would increase the magnetic flux and so on.
• There would be an infinite current...a current of infinite energy! But this break the principle of conservation of energy! This example shows how the minus sign of the Lenz's law is essential.