Practice Test Chapter 15. The Sun, planets and their moons, and a large collection of smaller objects such as asteroids, comets, and meteors are, together,

Practice TestPractice Test

Chapter 15Chapter 15

The Sun, planets and their moons, and The Sun, planets and their moons, and a large collection of smaller objects a large collection of smaller objects

such as asteroids, comets, and such as asteroids, comets, and meteors are, together, called the:meteors are, together, called the:

A.A. universe.universe.

B.B. galaxy.galaxy.

C.C. solar system.solar system.

D.D. nebulae.nebulae.

A unit used to measure long distances, equivalent to the distance from the Sun to Earth, is known as the:a. light year.b. cosmic scale.c. astronomical unit.d. sidereal year.

Terrestrial planets include all of the following EXCEPT:a. Mercury.b. Venus.c. Earth.d. Jupiter.

The gas planets include all of the following EXCEPT:a. Jupiter.b. Venus.c. Saturn.d. Uranus.

All of these objects in the night sky are seen because they reflect light EXCEPT:a. Earth’s moon.b. Venus.c. stars.d. Mercury.

A “shooting star” is seen when this object enters Earth’s atmosphere and is vaporized:a. a comet.b. a planetary satellite.c. an asteroid.d. a meteor.

Of the planets shown, Of the planets shown, the one which the one which requires the longest requires the longest time for one time for one revolution of the sun revolution of the sun is:is:

a.a. Mars.Mars. b.b. Venus.Venus. c.c. Earth.Earth. d.d. Mercury.Mercury.

The force of gravity between two objects will be greatest if their masses are:a. small and they far apart.b. large and they are close together.c. large and they are far apart.d. small and they are close together.

The asteroid belt is located between the planets:a. Mercury and Venus.b. Earth and Mars.c. Mars and Jupiter.d. Saturn and Uranus.

The diagram which The diagram which best represents the best represents the comparison between comparison between the diameters of the the diameters of the moon and Earth is:moon and Earth is:

A. 1A. 1 b.b. 22 c.c. 33 d.d. 44

It would be difficult to live on the moon because it lacks all of the following EXCEPT:a. air.b. water.c. gravity.d. normal temperatures.

Practice TestPractice Test

Chapter 16Chapter 16

The phrase “a giant, hot ball of gases” best describes a:a. planet.b. moon.c. star.d. meteorite.

The source of the Sun’s heat and light energy is:a. combustion of helium gas.b. fusion of hydrogen nuclei.c. gravitational pressure.d. burning of fossil fuels.

The main characteristics used to classify stars include all of the following EXCEPT:a. shape.b. brightness.c. color.d. temperature.

The color of the hottest stars is:a. red.b. orange.c. yellow.d. blue.

By size, the star known as our Sun is classified as:a. supergiant.b. giant.c. average.d. dwarf.

Scientists measure distances beyond our solar system (such as the distance between two stars) using these units:a. metersb. kilometersc. astronomical unitsd. light years

According to the H-R According to the H-R diagram in Figure 16-diagram in Figure 16-1A, the areas labeled 1A, the areas labeled B and E would be B and E would be classified as:classified as:

a.a. red and blue red and blue supergiantssupergiants

b.b. the main the main sequence.sequence.

c.c. white dwarfs.white dwarfs.

d.d. red giants.red giants.

According to the H-R According to the H-R diagram in Figure 16-diagram in Figure 16-1A, the areas labeled 1A, the areas labeled C and D would be C and D would be classified as:classified as:

a.a. red and blue red and blue supergiants.supergiants.

b.b. white dwarfs.white dwarfs.

c.c. the main the main sequence.sequence.

d.d. red giants.red giants.

As a group, stars As a group, stars known as main known as main sequence stars on an sequence stars on an H-R diagram are best H-R diagram are best described as being:described as being:

a.a. hotter.hotter. b.b. larger.larger. c.c. stable.stable. d.d. brighter.brighter.

The explosion of a very large star is known as a:a. black hole.b. white dwarf.c. neutron star.d. supernova.

A star begins to form when gravitational forces cause denser regions of a huge cloud of gas and dust to collapse. The earliest stage of a star’s life cycle is called the:a. protostar.b. red giant.c. white dwarf.d. supernova.

When the core of a star runs out of hydrogen:a. nuclear fusion stops and the star stops producing light.b. the core contracts, raising the temperature so that other fusion reactions occur.c. the star is immediately crushed into a black hole.d. the star becomes a white dwarf and then a red giant.

Chapter 16Chapter 16

Math ProblemsMath Problems

Sirius is about 8.8 light years from Earth. If one light year equals 9.46 ´ 1012 kilometers, how far is Sirius from Earth, measured in kilometers?a. 8.3 ´ 1013 kilometersb. 1.1 ´ 1013 kilometersc. 8.3 ´ 1011 kilometersd. 1.1 ´ 1011 kilometers

The distance from Earth to the star Proxima Centauri is 4.01 ´ 1013 kilometers. What is this distance in light years? One light year is equal to 9.46 ´ 1012 kilometers.a. 0.424 light yearsb. 4.24 light yearsc. 42.4 light yearsd. 424 light years

If you were traveling at 30 kilometers per second, how long would it take to reach Proxima Centauri, the nearest star to Earth other than our Sun? Proxima Centauri is 4.01 ´ 1013 kilometers from Earth. Hint: there are 31,557,600 seconds in one year.a. Approximately 134 yearsb. Approximately 4,240 yearsc. Approximately 42,400 yearsd. Approximately 1,340,000,000,000 years