Is magical energy = non magical energy?

[Romaji]

I was thinking about the idea that magic energy is an exact one-to-one with non magic energy.

Hence, the difficulty of doing a magic act in terms of how much "power" it takes out of you is equivalent to how much non-magical energy would be theoretically used to do that.
Thoughts about just how much this magic energy converts to non magic units of energy?

[dorotheia]

[Romaji]

But is it?
Just how much energy would it take to turn a human into a shark?
Is that spell cast from the wizards power, or is the powers that be gave it a boost?