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BIO Predict/Calculate Consider the physical situation illustrated in Figure 25-41. (a) Is Enin the incident laser beam greater than, less than, or the same as Erms where the beam hits the retina? Explain. (b) If the intensity of the beam at the retina is equal to the damage threshold, 1.0 × 10·2 W/cm2, what is the value of Erms at that location? (c) If the diameter of the spot on the retina is reduced by a factor of 2, by what factor does the intensity increase? By what factor does Erms increase?
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