PHY 303L Lecture : problemset11
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Rashid (sar3553) hw11 optics storr (37537) Multiple-choice questions may continue on the next column or page nd all choices before answering. A 20 mw laser has a beam diameter of. The speed of light is 2. 99792 108 m/s. Let : c = 2. 99792 108 m/s , and. = 851 nm = 8. 51 10 7 m . c = f . Let : p = 20 mw = 0. 02 w , and r = 1. 1 mm = 0. 0011 m . Let : c = 2. 99792 108 m/s . With the intensity i, which is also the average value of the poynting vector s, the average energy density u satis es i = s = c u , so u = From snell"s law, while travel in glass, speed of light is decreased by a factor of refraction index n; so the wavelength is also decreased due to the larger refraction index of glass.
