1. The problem statement, all variables and given/known data You stand 2.7 m from a 150 W light bulb that converts 5% of the electrical energy dissipated within it to light. (a) If the pupil of your eye is 5 mm in diameter, how much energy enters you eye per second? ___J 2. Relevant equations Iave= Pave/Area 3. The attempt at a solution I thought, since the total power output is 150W * 5% = 7.5, I could fine the Pave by Pave=Ptotal ^2 x 0.5 = 28.125. That did not work. I don't understand why this approach would not equal the answer, knowing that Power=Energy/sec, and we're assuming 1 sec. here. Thank you.