Solution: You are trying to estimate the efficiency of a lightbulb by measuring the power of the light emitted vs the power consumed by the bulb. You have a circular detector with a radius of 12 cm and you measure an intensity of 1.7 kW/m2 from a distance of 1.5 m. If the lightbulb pulls 150 W of power from an outlet, what is the efficiency of the lightbulb?

You are trying to estimate the efficiency of a lightbulb by measuring the power of the light emitted vs the power consumed by the bulb. You have a circular detector with a radius of 12 cm and you measure an intensity of 1.7 kW/m^{2} from a distance of 1.5 m. If the lightbulb pulls 150 W of power from an outlet, what is the efficiency of the lightbulb?