Photon Energy: A small gas laser of the type used in classrooms may radiate light at a power level of 2.0 mW. If the wavelength of the laser light is 642 nm, how many photons does it emit per second? (c = 3.0 × 108 m/s, h = 6.626 × 10-34 J ? s)
Fill in the blank(s) with the appropriate word(s).
6.5 × 1015
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Predicting an eclipse is easy because all you have to do is keep track of where the Moon crosses the ecliptic
a. True b. False Indicate whether the statement is true or false
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A) a B) b C) c D) d E) e
A ball falls to the ground from height h and bounces to height h'. Momentum is conserved in the ball-earth system
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