Question

I've got a test tomorrow morning help!
A 100.0 W incandescent light bulb emits about 1.6 J of energy as useful, visible light each second. What is its efficiency?

Answer 1

Answer:

The efficiency is just 0.016

Explanation:

The efficiency is given by the useful energy ÷ by the total energy.

1 W is the same that 1 joule per second

If you do the math:

1.6/100=0.016