Two light waves combine and produce a region of darkness. Which of the following must be true in that region?
A. The waves had different wavelengths
B. The waves were a half-wavelength out of phase
C. The waves were unpolarized
D. The waves came from the same source
Answer: B
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Indicate whether the statement is true or false
If a spring-operated gun can shoot a pellet to a height of 100. m on Earth, how high could the pellet rise if fired on the moon?
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