You are standing 2.5 m from a 150-W lightbulb. (a) If thepupil of your eye is a circle 5.0 mm in diameter, how much energyenters your eye per second? (Assume that 5.0% of the lightbulb’spower is converted to light.) (b) Repeat part (a) for the case of a1.0-mm-diameter laser beam with a power of 0.50 mW.

You are standing 2.5 m from a 150-W lightbulb. (a) If thepupil of your eye is a circle 5.0 mm in diameter, how much energyenters your eye per second? (Assume that 5.0% of the lightbulb’spower is converted to light.) (b) Repeat part (a) for the case of a1.0-mm-diameter laser beam with a power of 0.50 mW.

Inquiry into Physics

8th Edition

ISBN:9781337515863

Author:Ostdiek

Publisher:Ostdiek

Chapter8: Electromagnetism And Em Waves

Section: Chapter Questions

Problem 34Q

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