Suppose you have a light bulb that emits 50 watts of visible light. (note: this is not the case for a standard 50-watt light bulb, in which most of the 50 watts goes to heat and only about 5-7 watts is emitted as visible light.) how far away would you have to put the light bulb for it to have the same apparent brightness as alpha centauri a in our sky? (hint: use 50 watts as l in the inverse square law for light, and use the apparent brightness given above for alpha centauri a. then solve for the distance.)