College Physics: A Strategic Approach (4th Edition)
4th Edition
ISBN: 9780134609034
Author: Randall D. Knight (Professor Emeritus), Brian Jones, Stuart Field
Publisher: PEARSON
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Chapter 29, Problem 69GP
To determine
Minimum intensity of the laser beam during each pulse.
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A ruby laser emits an intense pulse of light that lasts a mere 10 ns . The light has a wavelength of 690 nm , and each pulse has an energy of 400 mJ .
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Fluorescence microscopy, discussed in Section 29.8, is an important tool in modern cell biology. A variation on this technique depends on a phenomenon known as two-photon excitation.If two photons are absorbed simultaneously (i.e., withinabout 10-16 s), their energies can add. A molecule that is normallyexcited by a 350 nm photon can be excited by two photonseach having half as much energy. For this process to beuseful, photons must illuminate the sample at the very high rateof at least 1029 photons/m2 # s. This is achieved by focusing alaser beam to a small spot and by concentrating the power ofthe laser into very short 110-13 s2 pulses that are fired 108 timeseach second. Suppose a biologist wants to use two-photon excitationto excite a molecular species that would be excited by500 nm light in normal one-photon fluorescence microscopy.What minimum intensity 1W/m2 2 must the laser beam haveduring each pulse?
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Chapter 29 Solutions
College Physics: A Strategic Approach (4th Edition)
Ch. 29 - Prob. 1CQCh. 29 - Prob. 2CQCh. 29 - Prob. 3CQCh. 29 - Prob. 4CQCh. 29 - Prob. 5CQCh. 29 - Prob. 6CQCh. 29 - Prob. 7CQCh. 29 - Prob. 8CQCh. 29 - Prob. 9CQCh. 29 - Prob. 10CQ
Ch. 29 - Prob. 11CQCh. 29 - Prob. 12CQCh. 29 - Prob. 13CQCh. 29 - Prob. 14CQCh. 29 - Prob. 15CQCh. 29 - Prob. 16CQCh. 29 - Prob. 17CQCh. 29 - Prob. 18CQCh. 29 - Prob. 20CQCh. 29 - Prob. 21CQCh. 29 - Prob. 22CQCh. 29 - Prob. 23CQCh. 29 - Prob. 24CQCh. 29 - Prob. 25CQCh. 29 - Prob. 27MCQCh. 29 - Prob. 28MCQCh. 29 - Prob. 29MCQCh. 29 - Prob. 30MCQCh. 29 - Prob. 31MCQCh. 29 - Prob. 32MCQCh. 29 - Prob. 1PCh. 29 - Prob. 2PCh. 29 - Prob. 3PCh. 29 - Prob. 4PCh. 29 - Prob. 5PCh. 29 - Prob. 6PCh. 29 - Prob. 7PCh. 29 - Prob. 8PCh. 29 - Prob. 9PCh. 29 - Prob. 10PCh. 29 - Prob. 11PCh. 29 - Prob. 12PCh. 29 - Prob. 13PCh. 29 - Prob. 14PCh. 29 - Prob. 15PCh. 29 - Prob. 16PCh. 29 - Prob. 17PCh. 29 - Prob. 18PCh. 29 - Prob. 19PCh. 29 - Prob. 20PCh. 29 - Prob. 21PCh. 29 - Prob. 22PCh. 29 - Prob. 23PCh. 29 - Prob. 24PCh. 29 - Prob. 25PCh. 29 - Prob. 27PCh. 29 - Prob. 28PCh. 29 - Prob. 29PCh. 29 - Prob. 30PCh. 29 - Prob. 31PCh. 29 - Prob. 32PCh. 29 - Prob. 33PCh. 29 - Prob. 34PCh. 29 - Prob. 35PCh. 29 - Prob. 36PCh. 29 - Prob. 37PCh. 29 - Prob. 39PCh. 29 - Prob. 40PCh. 29 - Prob. 41PCh. 29 - Prob. 42PCh. 29 - Prob. 43PCh. 29 - Prob. 45PCh. 29 - Prob. 46PCh. 29 - Prob. 47PCh. 29 - Prob. 48PCh. 29 - Prob. 49PCh. 29 - Prob. 50PCh. 29 - Prob. 51PCh. 29 - Prob. 52GPCh. 29 - Prob. 53GPCh. 29 - Prob. 54GPCh. 29 - Prob. 55GPCh. 29 - Prob. 56GPCh. 29 - Prob. 57GPCh. 29 - Prob. 58GPCh. 29 - Prob. 59GPCh. 29 - Prob. 60GPCh. 29 - Prob. 61GPCh. 29 - Prob. 62GPCh. 29 - Prob. 63GPCh. 29 - Prob. 64GPCh. 29 - Prob. 65GPCh. 29 - Prob. 66GPCh. 29 - Prob. 67GPCh. 29 - Prob. 69GPCh. 29 - Prob. 70MSPPCh. 29 - Prob. 71MSPPCh. 29 - Prob. 72MSPPCh. 29 - Prob. 73MSPPCh. 29 - Prob. 74MSPPCh. 29 - Prob. 75MSPPCh. 29 - Prob. 77MSPP
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