# Electronic – Why is power of a signal equal to square of that signal

analysispowersignal-theorytheory

Is there any logic as to why the power of a signal $$\\mathrm{x(t)}\$$ is taken as $$\\mathrm{x^2(t)}\$$?
I searched everywhere and there's no clue. My professor told: "It's a standard result so shut up!"

If the signal is represented as a voltage $$\v(t)\$$ or a current $$\i(t)\$$ and it is connected to a (1 ohm) resistor, the power dissipated in the resistor is proportional to $$\v^2(t)\$$ or $$\i^2(t)\$$.