# Question #9aff0

##### 1 Answer
Apr 30, 2017

The bulb has a fixed resistance. Domestic residences have a take nationally set voltage off the grid, usually 230 - 240 V depending where you are. So the current as well as the voltage the bulb is expected to draw is pre-set. And therefore power $P = V I$ can be calculated beforehand.

So the bulb will burn 75 J/s when drawing on the anticipated voltage.

That's none of the above.