What is the shape of the segmented mirrors of twin Keck Observatory telescopes, Gran Telescopio Canarias, and soon to be launched James Web Space Telescope?
a. spherical
b. hexagonal
c. rectangular
d. triangular
e. octagonal
b
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By how much is the FOV (field of view) enlarged from Figure 1 to Figure 3?
a. 100 b. 1 × 10^5 c. 1,000 d. 10,000
Standing Waves on a String: A string fixed at both ends is vibrating in one of its harmonics. If we now increase only the frequency at which the string is vibrating, which of the following characteristics do we also increase? (There could be more than one correct choice.)
A. the speed of the traveling waves on the string B. the period of the traveling waves on the string C. the wavelength of the traveling waves on the string D. the amplitude of the traveling waves on the string E. None of these
As stars evolve, their temperature and luminosity change; therefore, their spectral type (OBAF, etc.) changes as well.
Answer the following statement true (T) or false (F)
Today, we know that Newton's "laws" are
A) often incorrect when applied to molecular-sized objects. B) incapable of explaining the motions of the planets. C) in agreement with all known experimental evidence. D) no longer useful as scientific principles. E) often incorrect when applied to liquids.