Deck 18: The Stars

Question 1

A large modern astronomical telescope

A)is designed for high magnifications.
B)uses a single lens.
C)uses a single mirror.
D)uses a number of smaller mirrors.

Answer 1

uses a number of smaller mirrors.

Question 2

The two chief elements in the sun are

A)hydrogen and helium.
B)hydrogen and oxygen.
C)oxygen and nitrogen.
D)carbon and iron.

Answer 2

hydrogen and helium.

Question 3

The sun has

A)no atmosphere.
B)an atmosphere just above its surface only.
C)an atmosphere that extends only as far as the earth.
D)an atmosphere that extends well out into the solar system.

Answer 3

an atmosphere that extends well out into the solar system.

Question 4

The temperature of a star directly affects its

A)mass.
B)color.
C)composition.
D)age.

Question 5

Sunspots

A)are hotter than the rest of the solar surface.
B)are dark clouds floating in the solar atmosphere.
C)occur at random intervals.
D)are correlated with a number of terrestrial effects.

Question 6

Streams of protons and electrons from the sun do not affect

A)auroras.
B)the airglow of the night sky.
C)comet heads.
D)comet tails.

Question 7

Which of the following can appear as disks with the help of a telescope?

A)planets
B)main-sequence stars
C)red giants
D)supernovas

Question 8

Stars seem to twinkle because of

A)variations in their brightnesses.
B)variations in their colors.
C)turbulent movements in their atmospheres.
D)turbulent movements in the earth's atmosphere.

Question 9

A star whose spectral lines are shifted toward the red end of the spectrum

A)has a magnetic field.
B)is moving toward us.
C)is moving away from us.
D)is moving across our line of sight.

Question 10

Most stars have hot interiors surrounded by relatively cool atmospheres.The spectrum of such a star consists of

A)white lines against a dark background.
B)colored lines against a dark background.
C)dark lines against a white background.
D)dark lines against a colored background.

Question 11

The sun does not

A)have a magnetic field.
B)have a solid core.
C)revolve about an axis.
D)consist largely of ions.

Question 12

The source of the sun's energy is

A)radioactivity.
B)nuclear fission.
C)nuclear fusion.
D)combustion.

Question 13

The light the sun emits comes from

A)its interior.
B)a thin gas layer at its surface.
C)a thin liquid layer at its surface.
D)a thin solid layer at its surface.

Question 14

The interior of the sun consists of

A)liquid hydrogen.
B)molecules.
C)neutral atoms.
D)ions.

Question 15

The spectrum of a star can provide information of which one or more of the following?

A)the star's magnetic field
B)the star's temperature
C)the star's relative motion toward or away from us
D)the star's composition
E)All of the above

Question 16

Nuclear reactions in the sun's interior convert

A)hydrogen into helium.
B)helium into hydrogen.
C)carbon into nitrogen.
D)uranium into plutonium.

Question 17

Solar storms may affect

A)the earth's magnetic field.
B)electric transmission lines.
C)shortwave radio reception.
D)satellite electronics.
E)All of the above

Question 18

Auroras consist of

A)colored clouds.
B)comet tails.
C)excited gases in the lower atmosphere.
D)excited gases in the upper atmosphere.

Question 19

As compared with a large telescope mirror, a large telescope lens

A)is easier to support against sag.
B)does not disperse light.
C)can provide higher magnification.
D)has no advantages.

Question 20

The number of sunspots

A)remains approximately constant.
B)increases and decreases at random intervals.
C)increases and decreases in a yearly cycle.
D)increases and decreases in an 11-year cycle.

Question 21

The smallest of the following celestial objects is

A)a white dwarf.
B)a neutron star.
C)a planetary nebula.
D)the earth.

Question 22

The earth's magnetic field influences

A)comets.
B)meteoroids.
C)eclipses.
D)auroras.

Question 23

There is a surprisingly small variation among stellar

A)temperatures.
B)diameters.
C)densities.
D)masses.

Question 24

Stars whose intrinsic brightness and period of variation are related are called

A)pulsars.
B)Cepheid variables.
C)main-sequence stars.
D)red giants.

Question 25

The color of a relatively hot star is

A)white.
B)yellow.
C)blue.
D)red.

Question 26

Red giant stars

A)are not very bright.
B)have relatively low surface temperatures.
C)represent the initial stage in a star's cycle.
D)are among the densest objects in the universe.

Question 27

The distance of a star from the earth can be found

A)only if it is part of a double-star system.
B)by comparing its intrinsic and apparent brightnesses.
C)from its color.
D)from its position in the HR diagram.

Question 28

If we know the surface temperature and intrinsic brightness of a star we can find its

A)mass.
B)size.
C)age.
D)distance.

Question 29

The main sequence on the HR diagram includes

A)the sun.
B)white dwarfs.
C)red giants.
D)pulsars.

Question 30

Stars at the upper end of the main sequence have

A)high temperatures and large masses.
B)high temperatures and small masses.
C)low temperatures and large masses.
D)low temperatures and small masses.

Question 31

The star nearest to the sun is approximately

A)1 light-minute away.
B)4 light-years away.
C)300 light-years away.
D)4000 light-years away.

Question 32

A star must have a certain minimum mass in order that gravity squeeze its matter sufficiently to

A)hold it together as a single body.
B)produce a temperature high enough for it to glow.
C)produce a temperature high enough for nuclear reactions to start.
D)turn its interior into liquid hydrogen.

Question 33

In the HR diagram, most stars are

A)members of the main sequence.
B)red giants.
C)white dwarfs.
D)scattered at random.

Question 34

White dwarf stars are not

A)comparable in size with the earth.
B)comparable in mass with the sun.
C)extremely hot.
D)extremely bright.

Question 35

White dwarfs are stars that are

A)at the beginning of their life cycles.
B)in the middle of their life cycles.
C)at the end of their life cycles.
D)Any of these choices are correct.

Question 36

Binary stars are valuable to astronomers because they permit the determination of stellar

A)diameters.
B)distances.
C)masses.
D)temperatures.

Question 37

The less the mass of a main-sequence star, the

A)lower its density.
B)cooler it is.
C)brighter it is.
D)shorter its lifetime.

Question 38

Neutron stars are about

A)the size of a large house.
B)20 km in diameter.
C)the size of the moon.
D)the size of Jupiter.

Question 39

The sun will remain its present size and temperature

A)for a few thousand years longer.
B)for a few million years longer.
C)for a few billion years longer.
D)forever.

Question 40

The majority of main-sequence stars are

A)blue.
B)white.
C)yellow.
D)red.

Question 41

What keeps light from escaping from a black hole is its

A)strong electric field.
B)strong magnetic field.
C)strong gravitational field.
D)absorbing atmosphere.

Question 42

At the end of its period in the main sequence, a very heavy star

A)breaks up into several smaller stars.
B)cools down into a white dwarf.
C)expands into a red giant.
D)explodes into a supernova.

Question 43

Brown dwarfs are

A)visible to the naked eye.
B)present in the solar system.
C)relatively rare.
D)relatively common.

Question 44

Relatively few stars become

A)members of the main sequence.
B)red giants.
C)white dwarfs.
D)supernovas.

Question 45

The heaviest elements on the earth were produced in

A)the earth's interior.
B)the sun's interior.
C)supernova explosions.
D)black holes.

Question 46

The least common of the following are

A)white dwarfs.
B)red dwarfs.
C)brown dwarfs.
D)black dwarfs.

Question 47

At the end of its period in the main sequence, a star whose mass is near that of the sun

A)breaks up into several smaller stars.
B)cools down into a white dwarf.
C)expands into a red giant.
D)explodes into a supernova.

Question 48

Black holes

A)are all very small.
B)are all very large.
C)are present in the solar system.
D)can be detected when part of a binary system.

Question 49

A brown dwarf

A)has less mass than Jupiter.
B)is a member of the main sequence.
C)is on its way to becoming a black dwarf.
D)was never a true star.

Question 50

A supernova explosion may leave behind which one or more of the following?

A)a black hole
B)a neutron star
C)a pulsar
D)a red giant
E)Both A, B and C

Question 51

Pulsars are unlikely to be

A)small in size.
B)in rapid rotation.
C)composed largely of neutrons.
D)members of the main sequence.