Chapter 10- Stars, Galaxies and the Universe-PRACTICE TEST
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____1.Both reflecting and refracting telescopes are designed to
a. / break visible light into colors of the spectrum.b. / separate visible light from ultraviolet and radio waves.
c. / gather and focus visible light.
d. / work better with short-wavelength radiation.
____2.Reflecting telescopes differ from refracting telescopes in having
a. / no eyepiece lens.b. / two large objective lenses.
c. / a mirror instead of an objective lens.
d. / one large objective lens.
____3.A light-year is
a. / 365 days.b. / the distance light travels in a year.
c. / the distance from Earth to Proxima Centauri.
d. / the amount of light the sun produces in a year.
____4.Characteristics used to classify stars include
a. / distance, size, and color.b. / size, distance, and brightness.
c. / color, brightness, and distance.
d. / size, brightness, and temperature.
____5.What color are the coolest stars?
a. / blue-whiteb. / yellow
c. / red
d. / orange
____6.A star is born when
a. / a nebula expands.b. / helium and oxygen combine.
c. / nuclear fusion starts.
d. / a protostar begins to cool.
____7.The variable that determines whether a protostar becomes a star is its
a. / surface temperature.b. / age.
c. / mass.
d. / color and brightness.
____8.The lifetime of a star depends on its
a. / temperature.b. / absolute brightness.
c. / mass.
d. / apparent brightness.
____9.Depending on its mass, a star may live from about
a. / 1 million to 10 million years.b. / 5 million to 100 million years.
c. / 10 million to 200 billion years.
d. / 10 billion to 500 billion years.
____10.A supernova is the explosion of a dying
a. / medium-mass star.b. / high-mass star.
c. / protostar.
d. / low-mass star.
____11.From the cosmic background radiation, scientists can infer that, just after the big bang, the universe must have been
a. / very small.b. / hot.
c. / the same average temperature as it is today.
d. / cooler than it is today.
____12.More than half of all stars are members of groups of two or more stars called
a. / galaxies.b. / eclipsing binaries.
c. / star systems.
d. / star clusters.
____13.Which of the following is a major difference between elliptical galaxies and spiral galaxies?
a. / Elliptical galaxies have almost no gas or dust between the stars.b. / Elliptical galaxies vary more in shape than spiral galaxies.
c. / Spiral galaxies have almost no gas or dust between the stars.
d. / Spiral galaxies contain only old stars.
____14.The Milky Way galaxy is an example of a(n)
a. / spiral galaxy.b. / globular cluster.
c. / elliptical galaxy.
d. / irregular galaxy.
____15.According to Hubble’s law, the farther away a galaxy is,
a. / the faster it is moving toward us.b. / the slower it is moving toward us.
c. / the slower it is moving away from us.
d. / the faster it is moving away from us.
____16.The theory that astronomers have developed to describe the formation of the universe is called the
a. / big crunch theory.b. / collision-ring theory.
c. / galactic expansion theory.
d. / big bang theory.
____17.The solar system formed from
a. / an expanding galaxy.b. / a giant cloud of gas and dust.
c. / an enormous explosion.
d. / a black hole.
____18.The absolute brightness of a star depends on its
a. / distance and temperature.b. / size and temperature.
c. / color and temperature.
d. / distance and color.
____19.The Hertzsprung-Russell diagram shows that main-sequence stars
a. / are mostly hot and dim.b. / are mostly cool and bright.
c. / increase in brightness as they increase in temperature.
d. / decrease in brightness as they increase in temperature.
____20.The force that tends to pull together the matter in stars is
a. / gravity.b. / nuclear fusion.
c. / dark energy.
d. / dark matter.
____21.Why are many large optical telescopes located on mountains?
a. / to be closer to the starsb. / to be above part of the atmosphere
c. / because it is easier to build telescopes on mountains
d. / to be closer to city lights
____22.The mysterious force that may be causing the expansion of the universe to accelerate is called
a. / gravity.b. / dark matter.
c. / dark energy.
d. / cosmic background radiation.
____23.What is likely to happen to the universe in the future?
a. / It will contract.b. / It will remain the same size.
c. / It will expand forever.
d. / It will expand and then contract.
Modified True/False
Indicate whether the statement is true or false. If false, change the identified word or phrase to make the statement true.
____24.A reflecting telescope uses a mirror to focus light onto a small area. ______
____25.Most galaxies are moving away from each other, which means the universe is contracting. ______
____26.Astronomers typically measure distances to stars in units called kilometers. ______
____27.The brightness of a star as seen from Earth is its apparent brightness. ______
____28.The remains of a star that has no fuel but glows faintly is a black dwarf. ______
____29.Stars with less mass will last longer than stars with more mass. ______
____30.The sun is part of a(n) elliptical galaxy. ______
Completion
Complete each statement.
31.A device that detects radio waves from objects in space is called a(n) ______.
32.An object’s apparent change in position when viewed from two different places is called ______.
33.The length of a star’s life is determined by its ______.
34.A dying high-mass star can suddenly explode, becoming a(n) ______.
35.A galaxy that does not have a regular shape is classified as a(n) ______galaxy.
36.According to the big bang theory, the universe formed about ______years ago.
37.Telescopes work by collecting and focusing different forms of ______radiation.
38.Astronomers can determine a star’s chemical composition by using a(n) ______to observe the wavelengths of light the star emits.
39.The most massive stars collapse to form ______when they die.
40.A(n) ______galaxy has a characteristic pinwheel shape.
41.A spectrograph breaks the light from an object into a(n) ______, or range of different colors, and produces an image of it.
42.All stars begin as part of a large cloud of gas and dust called a(n) ______.
43.A protostar becomes a star when energy is released by the process of ______.
44.Our solar system is located in the ______galaxy.
45.______uses powers of ten to write very large or small numbers in shorter form.
46.Matter in space that does not give off electromagnetic radiation is called ______.
Short Answer
Use the diagram to answer each question.
47.Compare our sun to Alpha Centauri A in terms of color, absolute brightness, and surface temperature.
48.State how Barnard’s star and Mira are similar.
49.Name the stars on the diagram that are blue or blue-white.
50.Describe three features of the star Deneb.
51.Compare Betelgeuse and Barnard’s star in terms of size, color, and lifetime.
Use the diagram to answer each question.
52.How does a neutron star form?
53.What determines whether a star will form a black hole when it dies?
54.What is a supernova?
55.How does a star’s life begin?
56.When a star begins to run out of fuel, what two types of stars can it become?
57.What happens to low-mass and medium-mass stars when they run out of fuel?