Discuss several disadvantages of refractor versus reflector telescopes
What will be an ideal response?
Refractors must use lenses, and thus all suffer from some chromatic aberration; mirrors reflect all wavelengths of light the same. Correcting for chromatic aberration means including more optical surfaces, requiring more work than any reflector design, which includes the secondary mirrors. Large refractor lenses must be supported by their edges, which means they will flex under their own weight. Mirrors can be built much larger, and supported from the back with no light blockage. Lenses require two precision surfaces; mirrors only need one. Thick lenses will absorb some light, which is not an issue for mirrors.
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Modern astronomers suspect the corona is heated by
a. shock waves rising from below the photosphere. b. the solar wind. c. magnetic carpets. d. shock waves rising from below the photosphere, the solar wind, and the solar magnetic field. e. none of the others.
A car that travels twice as fast as another car when braking to a stop will skid
A) twice as far. B) four times as far. C) depends on the mass of the cars.
How can we best observe the Sun's chromosphere and corona?
A) The chromosphere is best observed with ultraviolet telescopes and the corona is best observed with X-ray telescopes. B) The chromosphere is best observed with infrared telescopes and the corona is best observed with ultraviolet telescopes. C) The chromosphere and corona are both best studied with visible light. D) The chromosphere and corona are both best studied with radio telescopes.
Repeatedly tap the side of a drinking glass with a spoon as you fill the glass with water and the pitch of the sound
A) increases. B) decreases. C) remains relatively constant.