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BIO You are standing 2.5 m from a 150-W lightbulb. (a) If the pupil of your eye is a circle 5.0 mm diameter, how much energy enters your eye per second? (Assume that 5.0% of the lightbulb’s power is converted to light.) (b) Repeat part (a) for the case of 1.0-mm- diameter laser beam with a power of 0.50 mW.
Figure 25-41
Problems 61 and 92
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