Question

a light bulb has an efficiency of 13.1%. how much light energy (not heat energy) is generated by the bulb every second if the bulb has a power of 8W?

Answer 1

please help me

Answer 2

Right, so first of all, power is a way of measuring energy per second, so if it's saying that the bulb has power 8W then 8 joules of energy is transferred every second. If it has 13.1% efficiency then 13.1% of those 8 joules goes into doing the useful job of producing light. So just find 13.1% of 8 and you'll have your answer.

Answer 3

so I need to multiply 8 joules by 13.1% ... giving me 104.8 j