My professor explained this phenomenon using the following statement and maths:

"Imagine you have a big current that suddenly becomes zero. This basically means that the rate of change of the current \( \frac{di(t)}{dt} \to \infty \).

So if you have an inductor \( \lim_{\frac{di(t)}{dt} \to \infty}v(t) = L \frac{di(t)}{dt} = \infty \) . In other words, you get a large voltage drop across the inductor in a small

**dt**time (thus creating a spike)."

I understand that, but how can an inductor that in one instant of a time it was under a 10V source supply suddenly get a voltage drop across the inductor in the range of Kilo volts? Where does this huge energy come from? The supply is only 10 volts, how can it exceed it?

It seems to me that it breaks the conservation of energy.