Astronomy Chapter 7

Earth's interior has been heated by 3 processes. These are: A) formation, differentiation and radioactivity. B) earthquakes, volcanoes and tectonics. C) convection, conduction and radiation. D) tides, sunlight and the rock cycle. E) greenhouse effect, dynamo effect and ozone depletion.

A

Earth's magnetic field: A) prevents charged particles in the solar wind from reaching the surface. B) is a remnant of the solar nebula's magnetic field. C) is weakening the Van Allen radiation belts. D) is the force behind plate tectonics. E) lines intersect the atmosphere at the equator.

A

How is the existence of Earth's unique atmosphere explained? A) The oxygen in Earth's atmosphere is a result of early life on Earth. B) Volcanic gases containing nitrogen were outgassed from Earth's interior. C) As Earth cooled, water vapor fell out of the atmosphere to form the oceans. D) Ultraviolet radiation from the Sun freed the hydrogen, allowing it to escape. E) When Earth formed, its atmosphere formed from the gases most common in the early solar system.

A

In what part of our atmosphere do we live? A) troposphere B) stratosphere C) mesosphere D) ionosphere E) exosphere

A

What effect does the Moon have on the Earth's day-night cycle? A) Tides cause the Earth's rotation to slow gradually, lengthening the day-night cycle. B) The pull of gravity from the Moon causes the Earth's rotation to speed up slightly, shortening the day-night cycle. C) The interaction between the magnetic fields of the Earth and the Moon causes the Earth's rotation to slow gradually, lengthening the day-night cycle. D) The Moon has no effect on the Earth's day-night cycle. E) The Sun controls Earth's day-night cycle and the Moon only affects this during eclipses.

A

Which body has the greatest gravitational pull on Earth? A) the Sun B) the Moon C) Mars D) Jupiter E) None has an impact, as all are too distant.

A

Which of the following layers of the Earth is unique among the terrestrial planets? A) hydrosphere B) ionosphere C) mantle D) crust E) core

A

Within Earth's atmosphere, in which layer does convection occur? A) the troposphere B) the stratosphere C) the mesosphere D) the ionosphere E) Convection occurs in all layers of Earth's atmosphere.

A

A region where a denser basaltic plate is subducted under a continental one is: A) the Himalayas. B) the Nazca Trench. C) the Mid-Atlantic Rift. D) Hawaii. E) the San Andreas Fault.

B

At what phase would tidal variation be the least during the entire day? A) new Moon B) first quarter C) waxing gibbous D) full Moon E) waning crescent

B

From the center outward, the correct order is: A) liquid iron inner core, solid nickel outer core, rocky mantle, silicate crust. B) solid metallic inner core, molten metal outer core, silicate mantle and crust. C) solid metal core, molten metal hydrosphere, rocky lithosphere, gases in atmosphere. D) solid rock core, liquid metal mantle, solid rock crust. E) molten metal hydrosphere, molten rock lithosphere, solid silicate crust.

B

In what scenario is the blue component of incoming sunlight scattered much more than any other color component? A) when the Sun is setting B) when the Sun is high in the sky C) when the Sun is rising D) during the night time E) during a solar eclipse

B

What is true of spring tides? A) The third quarter Moon would be high overhead at dawn. B) The difference between low and high tides would be greatest. C) There would be one high and one low tide each day. D) The Moon's phase will be first quarter. E) The difference between low and high tides would be smallest.

B

When strong solar winds are displaced poleward by our magnetic fields, we get: A) the Van Allen radiation belts. B) intense auroral displays. C) sunspots. D) hurricanes in the tropics. E) droughts and dust bowls in the American West.

B

Which statement about seismic waves is true? A) Only S waves can travel through liquid. B) P waves travel faster, and thus arrive sooner than do the S waves. C) In the shadow zones, neither type is observed. D) S waves can travel though the outer core, but P waves cannot. E) On the far side of the Earth, only the S waves on the surface can be detected.

B

Without the greenhouse effect operating in our atmosphere: A) we would not have to worry about any warming problems in the future. B) Earth would have an average temperature of -23 degrees Celsius. C) the ice in the polar regions would have melted long ago. D) the ozone layer would not be weakening. E) the Earth would have become much more like Venus long ago.

B

After two half-lives have passed, the ratio of a radioactive element to its daughter element is A) 0 to 4. B) 1 to 4. C) 1 to 3. D) 1 to 2. E) 1 to 1.

C

Almost all of our atmospheric gases lie in the: A) ionosphere. B) stratosphere. C) troposphere. D) ozone layer. E) mesosphere.

C

At what phase are the tides least noticeable? A) new Moon B) full Moon C) third quarter D) waxing crescent E) waning gibbous

C

In noting that our world is "differentiated," we mean that: A) the density of its materials decreases as you go downward toward the core. B) the Earth has evolved in a different pattern than any other planet. C) the iron and nickel core is denser than the silicate mantle and crust. D) radioactive heating in the core is at a slower pace than when the Earth was new. E) the Earth's magnetic field is different now in polarity than it was 700,000 years ago.

C

Seismic waves are most useful for mapping: A) the surface of Venus with Magellan. B) the surface of Mars with Global Surveyor. C) the Earth's core and mantle. D) the density of the hydrosphere. E) the depths of the oceans.

C

The critical part of the atmosphere for protecting life on the ground from excessive ultraviolet radiation is the: A) hydrosphere. B) troposphere. C) ozone layer. D) stratosphere. E) ionosphere.

C

The crust of the Earth is covered by about ________ water in the hydrosphere. A) 50% B) 60% C) 70% D) 80% E) 90%

C

The presence of a magnetic field is a good indication that: A) the Earth's interior is similar to Mercury's, as both have fields. B) a huge iron meteorite lies somewhere high up in the mantle, not in the core. C) we have a liquid metal outer core, spinning rapidly as we rotate. D) the Earth's interior must be completely molten to the center. E) the Earth's interior has had time to solidify, with a rigid bar magnet created.

C

The principal greenhouse gases in our present atmosphere are: A) hydrogen and helium. B) hydrogen sulfide and carbon disulfide. C) water vapor and carbon dioxide. D) methane and ammonia. E) sulfuric acid vapor and carbon dioxide.

C

The region around Earth where the magnetic field traps charged particles is the: A) ozone layer. B) exosphere. C) Van Allen radiation belts. D) corona. E) aurora borealis and australis.

C

The relative size of the atmosphere layer as compared to the solid part of Earth is most similar to: A) the peel of an orange as compared to the meat of the orange. B) the rind of a watermelon as compared to the meat of the watermelon. C) the skin of a grape as compared to the meat of the grape. D) the meat of a peach as compared to the pit of the peach. E) the meat of a cherry as compared to the pit of the cherry.

C

What can we conclude about the structure of Earth's interior knowing that the average density of Earth is higher than the average density of the rock on the continents and seafloor? A) that Earth's most dense material must be water B) that Earth's most dense material must be the seafloor and the continents C) that Earth's most dense material must be beneath the surface D) that Earth's least dense material must be the seafloor and the continents E) that Earth's least dense material must be beneath the surface

C

What gas is the primary constituent of our atmosphere? A) oxygen B) carbon dioxide C) nitrogen D) hydrogen E) helium

C

What is the process that physically transfers heat from a lower (hotter) to a higher (cooler) level? A) radiation B) translation C) convection D) reflection E) conduction

C

When water vapor condenses out at the cool tops of convection cells, what happens? A) It rains. B) It snows. C) Clouds form. D) A hurricane forms. E) A tropical depression forms.

C

Which major atmospheric component is chiefly a product of life processes? A) carbon dioxide B) water C) oxygen D) hydrogen sulfide E) nitrogen

C

Why is the sky blue? A) The atmosphere reflects the color of the oceans. B) The atmosphere reflects the light from the Sun. C) The atmosphere scatters the light from the Sun. D) The oceans refract the light from the Sun into the atmosphere. E) The oceans reflect the light from the Sun into the atmosphere.

C

Within Earth's atmosphere the ozone layer is located: A) in the troposphere. B) between the troposphere and the stratosphere. C) in the stratosphere. D) between the stratosphere and the mesosphere. E) in the mesosphere.

C

Above about 100 km, the high-energy portion of the Sun's radiation spectrum breaks down molecules into atoms. What is this part of Earth's atmosphere called? A) the troposphere B) the stratosphere C) the mesosphere D) the ionosphere E) the magnetosphere

D

Clouds form primarily at the boundary between: A) the stratosphere and the mesosphere. B) the mesosphere and the ionosphere. C) the troposphere and the mesosphere. D) the troposphere and the stratosphere. E) the hydrosphere and the troposphere.

D

Compared to the density of water, our Earth averages about: A) the same density, similar to Saturn. B) 3 times denser, much like our Moon. C) 4 times denser, similar to Mars. D) 5 times denser, like Mercury and Venus. E) 10 times denser, due to our core of iron and nickel.

D

Like other solid bodies in the solar system, Earth's surface was kept molten by: A) radioactivity. B) differentiation. C) convection. D) bombardment by small bodies. E) the solar nebula.

D

The Dynamo Theory holds that: A) lightning plays a major role in generating our magnetic fields. B) any other planet of similar density will also have a strong magnetic field. C) the Earth's core, like Mercury's, is now a solid, rigid bar magnet. D) magnetic fields are generated by rapidly spinning, fluid magnetic interiors. E) the Earth's magnetic field must switch polarities every few million years.

D

The greenhouse effect works by trapping: A) incoming ultraviolet radiation from the Sun. B) outgoing ultraviolet radiation from the Earth. C) incoming infrared radiation from the Sun. D) outgoing infrared radiation from the Earth. E) the heat from the Sun in Earth's atmosphere.

D

The oldest rocks on our crust are radioactively dated at about: A) 200 million years old. B) one billion years old. C) 2.7 billion years old. D) four billion years old. E) 4.6 billion years old.

D

We determine the structure of the Earth's core using: A) deep mine shafts. B) satellite imaging. C) radar and sonar. D) seismic wave data. E) magnetic resonance imaging.

D

What is the best description of the Earth's rotation over its entire history? A) It has periodically reversed directions, as the magnetic polarity reversals show. B) It has been constant over the entire history of the solar system. C) It undergoes abrupt changes, as the magnetic variations show. D) It has slowed down very gradually at about .0015 seconds per century. E) It has sped up at about .013 seconds per century.

D

What is the hole in the ozone layer thought to be caused by? A) greenhouse gases B) carbon dioxide C) water vapor D) CFCs E) acid rain

D

When two tectonic plates collide: A) they both stop moving. B) they always produce high mountain chains like the Himalayas. C) volcanoes always mark the boundary between them. D) they continue moving, producing a variety of large deformations. E) that region is safe from earthquakes, now that the plates are fixed.

D

Which of these gases are outgassed from our volcanic eruptions? A) oxygen, methane, ammonia B) carbon dioxide, water vapor, oxygen C) ammonia, water vapor, oxygen D) water vapor, methane, carbon dioxide E) helium, carbon dioxide, methane

D

Which parts of the Sun's radiation are responsible for heating Earth's surface? A) the radio and the ultraviolet B) the X-ray and the gamma ray C) the ultraviolet and the visible D) the visible and the infrared E) the infrared and the high energy particles

D

Which statement about seismic waves is FALSE? A) Both S and P waves can be detected by seismographs. B) Close to the epicenter, both S and P waves can be recorded. C) P waves travel faster, so the gap between their arrival times gives the source's distance. D) Only P waves can be detected in the shadow zone. E) S waves are blocked by the fluid outer core and cannot be observed on the other side of the planet from the epicenter.

D

Chlorofluorocarbons are primarily responsible for: A) global warming. B) convection. C) the greenhouse effect. D) atmospheric turbulence. E) ozone depletion.

E

From the Earth's center outward, the correct order is: A) core, hydrosphere, mantle, crust, atmosphere, magnetosphere. B) core, magnetosphere, mantle, crust, hydrosphere, atmosphere. C) core, crust, mantle, hydrosphere, atmosphere, magnetosphere. D) magnetosphere, core, mantle, crust, hydrosphere, atmosphere. E) core, mantle, crust, hydrosphere, atmosphere, magnetosphere.

E

The relative size of the mantle of Earth compared to the solid inner core of Earth is most similar to: A) the peel of an orange as compared to the meat of the orange. B) the rind of a watermelon as compared to the meat of the watermelon. C) the skin of a grape as compared to the meat of the grape. D) the meat of a peach as compared to the pit of the peach. E) the meat of a cherry as compared to the pit of the cherry.

E

What event triggered the dramatic increase in atmospheric carbon dioxide concentration seen over the last couple of centuries? A) the invention of CFCs B) the invention of the automobile C) the Tunguska meteoric impact D) the volcanic eruption in Iceland in 1783 E) the Industrial Revolution

E

What is the percentage of Earth's atmosphere (by volume) that is carbon dioxide (CO2)? A) 78 B) 21 C) 3 D) 0.9 E) 0.03

E

Which are places on Earth where convection is operating on a grand scale, creating conditions important to life on Earth? A) in the mantle B) in hot springs like Old Faithful C) in the troposphere, such as a summer thunderstorm D) at the thermal vents in the rift valleys E) All of the above are good examples.

E

Which of these is NOT a product of plate tectonics and hot spots? A) Hawaii B) Yellowstone and Old Faithful C) the Mid Atlantic Rift D) the Andes E) the Grand Canyon's eroded depths

E

Seismic S-waves can travel through Earth's liquid outer core.

False

The hydrosphere covers about 50% of the Earth's crust

False

The most abundant gas in Earth's atmosphere is oxygen.

False

The ozone layer blocks much of the Sun's visible radiation

False

The speed of the current warming trend is no different than those seen in fossil records.

False

When plates collide, they fuse together and come to rest.

False

Almost all the oxygen in Earth's atmosphere is unique among the planets in our solar system.

True

Collisions between low density continental plates create the tallest mountain chains, such as the Himalayas.

True

Greenhouse gases in our atmosphere trap just enough heat to keep the Earth's oceans liquid.

True

In the past, most of the landmass on Earth was concentrated in a single, large continent.

True

Infrared radiation is trapped close to our surface by the greenhouse effect.

True

Seismic P-waves can travel through both solid and liquid materials.

True

Subduction of higher density oceanic plates under the continents not only creates deep trenches but also tall volcanic chains ashore as well.

True

The Mid-Atlantic Ridge is the largest tectonic feature on our planet.

True

The continuing rise in the carbon dioxide in our atmosphere should cause our surface temperatures to rise.

True

The energy for plate tectonics comes primarily from radioactive decay in our core

True

The hydrosphere accounts in large part for the fact that our atmosphere is thinner than Venus's and contains far less carbon dioxide.

True

The ozone layer lies at the boundary of the stratosphere and mesosphere.

True

The three most abundant gases in our atmosphere are nitrogen, oxygen, and argon.

True

Trenches are areas where the denser oceanic plates are subducted beneath the leading edges of lighter continental ones.

True

We find from igneous rock dating that the polarity of the Earth's magnetic field has undergone many unexplained changes in periods of thousands of years.

True

When strong solar wind storms are diverted poleward by our magnetic fields, we often observe ________ in the ionosphere.

aurorae

When strong solar winds are directed poleward, we see ________ at night.

aurorae

In the process of breaking down the ozone layer, the chlorine from the CFCs acts as a(n) ________.

catylst

The age of rocks can be determined by comparing the quantity of a radioactive element and its stable ________ element.

daughter

Evidence that the Earth was nearly molten at one time comes from the differentiation of materials by ________ from core to crust.

density

A hot, molten body of different materials will become ________.

differentiated

The oldest rocks found on the Earth's surface date back about ________ billion years

four

The partial trapping of solar radiation is known as the ________.

greenhouse effect

The auroral displays occur in our ________.

ionosphere

Plate ________ is the process by which convection within the mantle reforms the crust above it.

tectonics

The ________ on the edges of the continents come from subduction of oceanic basalt beneath the advancing continental plate.

trenches