Problem: 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?

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Problem Details

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?

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What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Energy Carried by Electromagnetic Waves concept. You can view video lessons to learn Energy Carried by Electromagnetic Waves. Or if you need more Energy Carried by Electromagnetic Waves practice, you can also practice Energy Carried by Electromagnetic Waves practice problems.

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Our expert Physics tutor, Juan took 1 minute and 58 seconds to solve this problem. You can follow their steps in the video explanation above.