As the 21st century began, which of the following is a discovery made by astronomers?
A) The Universe has a center.
B) The expansion of the Universe is actually accelerating.
C) The Universe has an edge.
D) The expansion of the Universe has come to a halt.
B
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Galileo's observation of the satellites of Jupiter showed that ________.
A. the Moon was not a flawless sphere B. nothing orbited Earth C. there were objects that did not orbit Earth D. planets orbited the Sun E. None of these choices is correct.
In general, which type of planet would you expect to cause the largest Doppler shift in the spectrum of its star?
A) a massive planet that is close to its star B) a massive planet that is far from its star C) a low-mass planet that is close to its star D) a low-mass planet that is far from its star
Exhibit 17-1
The figure below shows a sine wave at one point of a string as a function of time.
?
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Use the exhibit to answer the following question(s).
Refer to Exhibit 17-1. Which of the graphs below shows a wave where the amplitude and frequency are each reduced in half?
A.
B.
C.
D.
E.
The vertical displacement of a string is given by y(x,t) = (6.00 mm) cos[(3.25 m-1)x – (7.22 s-1)t]. What is the period of the wave?
A) 7.22 s B) 1.93 s C) 0.870 s D) 0.308 s E) 0.139 s