astro quiz 8

The largest part (by volume) of the Earth is its atmosphere core mantle oceanic crust continental crust

mantle

Scientists now understand that the Earth consists of layers, with the densest materials in the core. What allowed the differentiation of the Earth's layers to happen? this is an unsolved problem; scientists have no good ideas about this at all a giant rock from space hit the Earth and made a huge hole almost to the center, through which material could move continental drift and plate tectonics made this happen the early Earth must have been so hot it was like a liquid and heavier things sank to the middle this is one of the things that happened in the last few thousand years because of global warming

the early Earth must have been so hot it was like a liquid and heavier things sank to the middle

One way in which the ozone layer is useful for life forms on the Earth's surface is that it: keeps the heat of the Sun from escaping, making the Earth a bit warmer is so thick that meteors from space all burn up there, regardless of size absorbs ultra-violet light, preventing much of it from reaching the surface glows brilliantly at sunset, making scenes that lovers can enjoy presses down on the continental plates, and makes it more difficult for them to slip

absorbs ultra-violet light, preventing much of it from reaching the surface

Which of the following is a way we believe that the early atmosphere of the Earth differed from the atmosphere we have today? there was little if any free oxygen early on there was no ozone layer early on there was probably more carbon dioxide early on than there is today all of the above none of the above

all of the above

The average temperature on planet Earth is higher than you would expect just from the heating of sunlight alone. What is the explanation for this? solid material hitting the Earth from space heats it up the heat given off by living things makes our planet warmer the rubbing of the continental plates warms up the Earth's surface we have no explanation for this higher temperature and that has scientists worried carbon dioxide (and other gases) in the atmosphere cause a greenhouse effect

carbon dioxide (and other gases) in the atmosphere cause a greenhouse effect

If no one has ever visited the core of the Earth, how do we know that it is made of metals? spectroscopy allows us to tell what the core is made of by analyzing the light we receive you can't fool me; there is NO evidence that the Earth's core has metals core material seeps up through volcanoes in the crust circulating liquid metals in the core set up a large (measurable) magnetic field the amount of radioactivity shows metals must be present; only metals are radioactive

circulating liquid metals in the core set up a large (measurable) magnetic field

Which of the following points about our planet's atmosphere is FALSE? it is slowly leaking atoms into space from its outermost regions warm air rises and cool air descends within it, setting up circulating currents it is made mostly of nitrogen its mass is a substantial part of the mass of the Earth one of its layers helps keep much of the ultraviolet radiation from space from reaching the surface

its mass is a substantial part of the mass of the Earth

Which of the following statements about the Earth's magnetosphere is FALSE? it is generated by circulating liquid metal inside the Earth's core it was first detected in space by the Explorer 1 satellite its shape and size are the same on the sides facing toward and away from the Sun it extends into space over a region much bigger than the diameter of the Earth it contains particles that come mainly from the solar wind

its shape and size are the same on the sides facing toward and away from the Sun

An important way that scientists have been able to study the interior of the Earth is by: digging deep trenches at the bottom of the ocean, which is a lot closer to the planet's center there is no way we can study's the Earth's deep interior at the present time using spacecraft that can detect strong radio waves coming from the center studying the exterior, which is made of exactly the same material measuring how seismic waves are transmitted through the Earth

measuring how seismic waves are transmitted through the Earth

Earthquake producing faults are much more likely to be found: where the Earth's magnetic field touches the planet's surface in the southern hemisphere of the Earth, where there is more water on the boundaries of continental plates, where they meet other plates you can't fool me, such faults are equally likely anywhere on the Earth's crust in smooth continental desert areas

on the boundaries of continental plates, where they meet other plates

Regions where the continents or the sea floor are pulling apart are called enterprise zones rift zones convection zones subduction zones magnetospheric zones

rift zones

Scientists have been concerned about a set of industrial chemicals called CFC's (chlorofluorocarbons) because they: rise into the atmosphere and destroy ozone increase the chances of volcanic eruptions where the Earth's crust is thin rise into the atmosphere and absorb x-rays from space, which we need down here rise into the atmosphere and keep the Earth's heat from escaping seep into the groundwater and increase the chances of earthquakes

rise into the atmosphere and destroy ozone

Today, scientists believe that the main reason the Earth has had periodic ice ages is: no one has any good theories about the cause of the ice ages the grinding of continental plates against each other over the centuries slow changes in the tilt of our planet's axis of rotation the fact that the Moon is slowly moving toward the Earth and drawing off heat changes in the composition of the Earth's atmosphere that affect the ozone layer

slow changes in the tilt of our planet's axis of rotation

According to the theory of plate tectonics, the rubbing of the waters of the Earth across its crust is speeding up its rotation the continents are moving but the ocean floor is not, leading to great friction earthquakes are caused by huge waves that come up from inside the molten core of the Earth the liquid metal inside the Earth is developing plates of solid metallic material, which contribute to the Earth's magnetic field slow motions within the mantle of the Earth move large sections of the crust around

slow motions within the mantle of the Earth move large sections of the crust around

The Moon is heavily cratered, but the Earth which "lives next door" is NOT. Why? the active geology and weather on Earth destroy traces of impacts over millions of years the magnetism of the Moon is more likely to attract metallic objects to hit it all objects from space (no matter what their size) burn up in the Earth's atmosphere the Earth is heavily cratered, but all the craters are under the ocean the craters on the Moon are the result of active volcanoes; the Earth has few volcanoes compared to the Moon

the active geology and weather on Earth destroy traces of impacts over millions of years

An increase in the Earth's temperature by several degrees Celsius would result in: the Moon coming closer to the Earth a huge increase in the rate of motion of the continental plates and far more earthquakes an increase in the Earth's magnetism, increasing the size of the VanAllen belts the melting of many glaciers, a rise in sea levels, and more flooding of towns near the coasts of the continents a new ice age

the melting of many glaciers, a rise in sea levels, and more flooding of towns near the coasts of the continents

The process of convection involves: water shaping deep cuts into the Earth's crust, such as the Grand Canyon ultraviolet rays changing regular oxygen into ozone the slow upward flow of warmer material and downward flow of cooler material the electrocution of prisoners convicted of really terrible crimes the trapping of charged particles in a magnetic zone

the slow upward flow of warmer material and downward flow of cooler material

In which region of the Earth's atmosphere have you spent most of your life? the troposphere the ionosphere the stratosphere the mesosphere the ozone layer

the troposphere

A spot where magma rises to the surface can be seen as a: subduction zone swamp volcano fault continental plate

volcano

Mountains on Earth often have sharp peaks and edges to them, while mountains on the Moon look smooth and kind of dull in comparison. What gives the Earth's mountains their dramatically sharp shapes? rocks falling from space hit the mountains and shape them this is an unsolved problem in science wind, water, and ice flow over the Earth's mountains and erode them the Earth's magnetic field is responsible for all the shapes on the surface earthquakes in the mountain regions break big mountains into smaller ones

wind, water, and ice flow over the Earth's mountains and erode them