the velocity of a galaxy can be measured by measuring
A how fast it moves across the sky
B how many lines occur in its spectrum
C the shift in the pattern of lines in its spectrum
D how fast its apparent size decreases
if a yellow spectral line is Doppler shifted toward the blue end of the spectrum:
A the source is moving away from you.
B the source is moving toward you.
C the distance between you and the source is increasing.
D the distance between you and the source is decreasing.
the Doppler effect causes light from a source moving away to be
A shifted to shorter wavelengths.
B shifted to longer wavelengths.
C changed in velocity.
D both (a) and (c) above.
E both (b) and (c) above.
light from an object moving toward you, as compared to an unmoving light source, is
A unchanged
B bluer
C redder
D brighter
imagine you observe the red shifts of two galaxies, galaxy a at 15,000 km/sec and galaxy b at 60,000 km/sec. you can conclude that
A galaxy a is twice as far away as galaxy b.
B galaxy b is twice as far away as galaxy a.
C galaxy a is four times as far away as galaxy b.
D galaxy b is four times as far away as galaxy a
the Doppler shift explains
A change in wavelength due to a moving light source
B change in frequency due to a moving light source
C change in pitch due to a moving sound source
D all of these
the measurement of the Doppler shift of a star allows us to determine its
A temperature
B total velocity
C radial velocity
D proper motion
a light emitting object moving toward an observer will appear to the observer to be emitting waves that are
A longer than normal
B shorter than normal
C unchanged from normal
D different from normal only if the observer is also moving
the light of a distant galaxy has been shifted so that
A its speed is decreased
B its wavelength is decreased
C its wavelength is increased
D its relative brightness is increased
a red shift in the spectrum of a distant galaxy indicates that the galaxy is
A hot.
B cool.
C receding from us.
D advancing toward us.
E none of the above.
the Doppler shift of light from an object approaching us would
A decrease the wavelength
B decrease the frequency
C increase the speed
D increase the amplitude
the Doppler shift of a wave can be used to determine
A the velocity of the source of the wave
B the velocity of the waves
C the distance of the source
D the temperature of the source.
the Doppler effect is used to
A measure the radial velocity of a star.
B detect and study binary stars.
C measure the rotation of the sun.
D two of the above.
E all of the above.
the speed of a distant galaxy can be determined by measuring
A the shift in the pattern of its colors
B its motion in the sky during several years of observation
C the period of its light variation
D its changing distance in the Hubble diagram during several years
a star moving toward us which is otherwise identical to the sun would appear, compared to the sun,
A fainter in actual brightness
B brighter in actual brightness
C bluer
D redder
the pattern of colors of all galaxies outside our cluster of galaxies is
A shifted toward the blue
B shifted toward the red
C identical with the pattern of our own galaxy
D impossible to interpret
a star moving away from the Earth will have a spectrum containing
A red shifted lines.
B blue shifted lines.
C unshifted lines.
D weak lines.
if we see a blue shift for a star in our galaxy, the star
A must be cooler-than-normal.
B must be moving away from us faster than is normal.
C must be moving toward us.
D must be giving off more blue light than a normal star.
E both (a) and (d) above; they mean the same thing.
a red shift in the spectrum of a distant galaxy indicates that it is
A advancing toward the observer
B receding from the observer
C moving across the observer's line of sight
D standing still
when light is Doppler shifted by motion of the source away from the detect
A the measured frequency is higher than the emitted frequency
B the frequency remains the same, but the wavelength is shortened, compared to the emitted radiation
C the detected wavelength is longer than the emitted wavelength
D the speed of the radiation is reduced below the emitted speed
the spectral lines of a star are observed to be shifted toward the blue.
A the star is approaching us
B the star is receding from us
C the star is very hot
D the star is rather cool
the Doppler effect is the change in the wavelength of light caused by the source
A being in an intense magnetic field
B moving with respect to the observer
C being within a high gravitational field
D being embedded in a cloud of dust and gas
if a celestial object is "red shifted,"
A its spectrum shows a Doppler shift to shorter wavelengths
B its spectrum shows a Doppler shift to longer wavelengths
C its light has been filtered through interstellar dust
D its color index must be greater than 1.0
the velocity of a star toward or away from the Earth can be determined by measuring the
A color of the star
B shift of its spectral lines
C brightness of the star
D cannot be determined
the red shift that you measure in the spectrum of a galaxy tells you
A how large it is.
B how much mass it has, in total.
C the temperatures of the stars it contains.
D it is moving away from us and its speed of recession.
E it is moving toward us and its speed of approach.
when a star's spectrum is red shifted as a result of the Doppler effect, we know that the star is
A much cooler than average.
B slightly cooler than average.
C about average temperature.
D hotter than average.
E moving away from Earth.
if the distance between you and a star is decreasing, the wavelength of its spectral lines will:
A be the same as if the motion were not occurring.
B be longer than if the motion were not occurring.
C be shorter than if the motion were not occurring.
D be longer or shorter depending on the distance of the star.
the velocities determined from the shifted pattern of colors of a galaxy is a measure of
A its total velocity
B its velocity relative to the center of the universe
C that part of its velocity relative to us which brings it closer or further from us
D our position relative to the center of the universe
the tangential velocity of a star can be determined from its
A radial velocity and distance
B apparent brightness and parallax
C proper motion and distance
D proper motion and spectral type
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