ACT Science : Earth and Space Sciences

Study concepts, example questions & explanations for ACT Science

varsity tutors app store varsity tutors android store varsity tutors ibooks store

Example Questions

Example Question #41 : Earth And Space Sciences

Earth’s moon rotates like a satellite around Earth. It is the fifth largest moon in the Solar System and is best seen at night. The Earth’s moon is about 384,400 km from Earth and has an orbital period of twenty-seven days. Most scientists agree that the Moon formed about 4.5 billion years ago; however, there are several conflicting theories on the moon’s origin. Below two scientists discuss what they believe to be true.

 

Scientist 1 

The Fission Theory states that the Moon and Earth were once the same formation. A part of the formation separated from Earth and became the moon. The formation that broke off to form the moon most likely came from the Pacific Ocean Basin. The rock densities of the moon are similar to the rock densities of the Earth’s mantle. This is because the part that broke off from the Earth to form the moon broke off from the outer part of the Earth’s mantle. The theory that the Moon and Earth formed separately is highly unlikely. For this theory to be true, Earth’s gravitational field would have had to pull the moon into orbit. This is unlikely because it would have required a very particular set up. Most objects that come into the Earth’s gravitational field have elliptical orbits. If the Moon was pulled into orbit with the Earth, it would have a comet-like elliptical orbit—which it does not.

 

Scientist 2

The Impactor Theory states that a small planet collided with the Earth just after the solar system was formed. This caused large amounts of materials from the outer shell of both planets to break off. This debris started orbiting the Earth and forming one collective body of material. That collective piece is what we now call the moon. The lunar rocks studied are burnt, implying they were heated at one time. This would make sense because when the small planet and Earth collide, the material became heated due to impact. In addition, the Moon does not have a magnetic field like Earth, but some of the rocks on the surface of the Moon hint the Moon could have had some sort of magnetic qualities at one time. This is because the Moon was partially made up of Earth’s outer rocks.

What do both the viewpoint of Scientist 1 and the viewpoint of Scientist 2 have in common?

Possible Answers:

The two viewpoints have nothing in common.

A small planet collided with the Earth prior to the existence of the Moon.

They both agree that the Moon should have a comet-like elliptical orbit.

It is unlikely, but possible, that the Moon and Earth formed separately.

Both agree that pieces of the Earth were used in the formation of the Moon.

Correct answer:

Both agree that pieces of the Earth were used in the formation of the Moon.

Explanation:

Both Scientists agree pieces of the Earth were used to create the Moon. The viewpoints differ on if the Earth was solely used as opposed to the Earth and an additional planet. 

Example Question #42 : Earth And Space Sciences

Earth’s moon rotates like a satellite around Earth. It is the fifth largest moon in the Solar System and is best seen at night. The Earth’s moon is about 384,400 km from Earth and has an orbital period of twenty-seven days. Most scientists agree that the Moon formed about 4.5 billion years ago; however, there are several conflicting theories on the moon’s origin. Below two scientists discuss what they believe to be true.

 

Scientist 1 

The Fission Theory states that the Moon and Earth were once the same formation. A part of the formation separated from Earth and became the moon. The formation that broke off to form the moon most likely came from the Pacific Ocean Basin. The rock densities of the moon are similar to the rock densities of the Earth’s mantle. This is because the part that broke off from the Earth to form the moon broke off from the outer part of the Earth’s mantle. The theory that the Moon and Earth formed separately is highly unlikely. For this theory to be true, Earth’s gravitational field would have had to pull the moon into orbit. This is unlikely because it would have required a very particular set up. Most objects that come into the Earth’s gravitational field have elliptical orbits. If the Moon was pulled into orbit with the Earth, it would have a comet-like elliptical orbit—which it does not.

 

Scientist 2

The Impactor Theory states that a small planet collided with the Earth just after the solar system was formed. This caused large amounts of materials from the outer shell of both planets to break off. This debris started orbiting the Earth and forming one collective body of material. That collective piece is what we now call the moon. The lunar rocks studied are burnt, implying they were heated at one time. This would make sense because when the small planet and Earth collide, the material became heated due to impact. In addition, the Moon does not have a magnetic field like Earth, but some of the rocks on the surface of the Moon hint the Moon could have had some sort of magnetic qualities at one time. This is because the Moon was partially made up of Earth’s outer rocks.

If research concluded that the Moon's composition was the same as the Earth's composition, which viewpoint would this support? 

Possible Answers:

Not enough information to conclude 

Neither Scientist 1 or Scientist 2

Scientist 2

Scientist 1

Both Scientist 1 and Scientist 2

Correct answer:

Scientist 1

Explanation:

Scientist 1 believes the Moon was created solely from the Earth. This would be supported if the composition of the Moon was the same as the Earth. Scientist 2 believes the Earth and another planet merged to create the Moon; therefore Scientist 2 would want to see data showing the Moon had some of Earth's composition, but not identical.

Example Question #43 : Earth And Space Sciences

Earth’s moon rotates like a satellite around Earth. It is the fifth largest moon in the Solar System and is best seen at night. The Earth’s moon is about 384,400 km from Earth and has an orbital period of twenty-seven days. Most scientists agree that the Moon formed about 4.5 billion years ago; however, there are several conflicting theories on the moon’s origin. Below two scientists discuss what they believe to be true.

 

Scientist 1 

The Fission Theory states that the Moon and Earth were once the same formation. A part of the formation separated from Earth and became the moon. The formation that broke off to form the moon most likely came from the Pacific Ocean Basin. The rock densities of the moon are similar to the rock densities of the Earth’s mantle. This is because the part that broke off from the Earth to form the moon broke off from the outer part of the Earth’s mantle. The theory that the Moon and Earth formed separately is highly unlikely. For this theory to be true, Earth’s gravitational field would have had to pull the moon into orbit. This is unlikely because it would have required a very particular set up. Most objects that come into the Earth’s gravitational field have elliptical orbits. If the Moon was pulled into orbit with the Earth, it would have a comet-like elliptical orbit—which it does not.

 

Scientist 2

The Impactor Theory states that a small planet collided with the Earth just after the solar system was formed. This caused large amounts of materials from the outer shell of both planets to break off. This debris started orbiting the Earth and forming one collective body of material. That collective piece is what we now call the moon. The lunar rocks studied are burnt, implying they were heated at one time. This would make sense because when the small planet and Earth collide, the material became heated due to impact. In addition, the Moon does not have a magnetic field like Earth, but some of the rocks on the surface of the Moon hint the Moon could have had some sort of magnetic qualities at one time. This is because the Moon was partially made up of Earth’s outer rocks.

What piece of information would help support Scientist 1's point of view?

Possible Answers:

The Moon has two vastly different environments that exist on opposite sides of the planet.

The Moon's composition has some simliarities with the composition of Mars.

The Earth actually rotates around the Moon.

Research discovers the Moon has a magnetic field similar to Earth's magnetic field.

The moon has a comet-like eplliptical orbit.

Correct answer:

Research discovers the Moon has a magnetic field similar to Earth's magnetic field.

Explanation:

Scientist 1 believes the Moon is made up of solely material from the Earth; therefore similar magnetic fields would suport this notion.

Example Question #44 : Earth And Space Sciences

Earth’s moon rotates like a satellite around Earth. It is the fifth largest moon in the Solar System and is best seen at night. The Earth’s moon is about 384,400 km from Earth and has an orbital period of twenty-seven days. Most scientists agree that the Moon formed about 4.5 billion years ago; however, there are several conflicting theories on the moon’s origin. Below two scientists discuss what they believe to be true.

 

Scientist 1 

The Fission Theory states that the Moon and Earth were once the same formation. A part of the formation separated from Earth and became the moon. The formation that broke off to form the moon most likely came from the Pacific Ocean Basin. The rock densities of the moon are similar to the rock densities of the Earth’s mantle. This is because the part that broke off from the Earth to form the moon broke off from the outer part of the Earth’s mantle. The theory that the Moon and Earth formed separately is highly unlikely. For this theory to be true, Earth’s gravitational field would have had to pull the moon into orbit. This is unlikely because it would have required a very particular set up. Most objects that come into the Earth’s gravitational field have elliptical orbits. If the Moon was pulled into orbit with the Earth, it would have a comet-like elliptical orbit—which it does not.

 

Scientist 2

The Impactor Theory states that a small planet collided with the Earth just after the solar system was formed. This caused large amounts of materials from the outer shell of both planets to break off. This debris started orbiting the Earth and forming one collective body of material. That collective piece is what we now call the moon. The lunar rocks studied are burnt, implying they were heated at one time. This would make sense because when the small planet and Earth collide, the material became heated due to impact. In addition, the Moon does not have a magnetic field like Earth, but some of the rocks on the surface of the Moon hint the Moon could have had some sort of magnetic qualities at one time. This is because the Moon was partially made up of Earth’s outer rocks.

What evidence listed below could be used to support the viewpoints of both scientists?

Possible Answers:

The Pacific Ocean Basin

A third type of rock composition was found in the Moon

The dissimilar rock densities of the Earth and the Moon

The moon becomes the sixth largest moon in the Solar System

None of the options could support both viewpoints

Correct answer:

The Pacific Ocean Basin

Explanation:

The Pacific Ocean Basin can support the idea that part of the Earth broke off to create the Moon. The Pacific Ocean Basin can also support the idea that the Earth collided with another planet and resulted in a piece of the Earth breaking off.

Example Question #41 : Earth And Space Sciences

The cause of the extinction of dinosaurs 65 million years ago is currently debated. Some attribute the extinction to volcanic activity while others attribute it to asteroid or comet impact. Two scientists offer conflicting viewpoints on the most probable cause of the mass extinction.

 

Scientist A

The extinction of dinosaurs was most likely caused by the impact of an asteroid or large comet. Unusually high levels of the rare metal iridium (found in extraterrestrial material) have been discovered in a layer of clay deposited at just the time of the extinction. In addition, this layer of clay contained quartz grains with a crystal structure that has been distorted by exceedingly high pressures (almost certainly caused by an impact). This colossal impact brought about a period of severe cooling that affected dinosaur eggs rather than adult dinosaurs. Small reptiles could survive by protecting their minute eggs in a variety of ways. However, there was no way for dinosaurs to protect their large eggs against a quickly-changing climate.

 

Scientist B

The extinction of dinosaurs was most likely caused by a volcanic outburst. In general, volcanic eruptions can have potent effects on climate. In 1815 the volcano Tambora in Indonesia erupted, spreading a pall of dust around the globe that resulted in killing frosts around Europe. The much larger eruption that formed the Deccan basalts about 65 million years ago would have caused a deeper and more prolonged cooling that directly affected adult dinosaurs. The rare metal iridium has been found both in active volcanoes and in a layer of clay deposited around the time of the dinosaur extinction. Therefore the dinosaurs were most likely affected by a massive volcanic eruption.

Suppose it were recently discovered that the quartz grains mentioned in the passage actually belonged to a layer of clay deposited about 50 million years ago. This finding would most likely weaken the viewpoint(s) of __________.

Possible Answers:

scientist A only

both Scientist A and Scientist B

neither Scientist A nor Scientist B

scientist B only

Correct answer:

scientist A only

Explanation:

Only Scientist A mentions the quartz grains in support of his/her theory. Scientist A explains that the quartz grains were subjected to very high pressures caused by asteroid impact. The finding that these grains were from an entirely different layer of clay would weaken the argument of Scientist A.

Example Question #46 : How To Find Conflicting Viewpoints In Earth And Space Sciences

The cause of the extinction of dinosaurs 65 million years ago is currently debated. Some attribute the extinction to volcanic activity while others attribute it to asteroid or comet impact. Two scientists offer conflicting viewpoints on the most probable cause of the mass extinction.

 

Scientist A

The extinction of dinosaurs was most likely caused by the impact of an asteroid or large comet. Unusually high levels of the rare metal iridium (found in extraterrestrial material) have been discovered in a layer of clay deposited at just the time of the extinction. In addition, this layer of clay contained quartz grains with a crystal structure that has been distorted by exceedingly high pressures (almost certainly caused by an impact). This colossal impact brought about a period of severe cooling that affected dinosaur eggs rather than adult dinosaurs. Small reptiles could survive by protecting their minute eggs in a variety of ways. However, there was no way for dinosaurs to protect their large eggs against a quickly-changing climate.

 

Scientist B

The extinction of dinosaurs was most likely caused by a volcanic outburst. In general, volcanic eruptions can have potent effects on climate. In 1815 the volcano Tambora in Indonesia erupted, spreading a pall of dust around the globe that resulted in killing frosts around Europe. The much larger eruption that formed the Deccan basalts about 65 million years ago would have caused a deeper and more prolonged cooling that directly affected adult dinosaurs. The rare metal iridium has been found both in active volcanoes and in a layer of clay deposited around the time of the dinosaur extinction. Therefore the dinosaurs were most likely affected by a massive volcanic eruption.

Under high pressure, densely packed clay can be transformed into loosely packed clay. Suppose that the density of clay found in the layer corresponding to 65 million years ago were abnormally low. This finding would support the viewpoint of __________.

Possible Answers:

scientist B only

neither Scientist A nor Scientist B

scientist A only

both Scientist A and Scientist B

Correct answer:

scientist A only

Explanation:

The presence of loosely packed clay would indicate that the layer had been subjected to high pressure. Since high pressure comes from asteroid impacts (according to the passage), this finding would support the hypothesis of Scientist A.

Example Question #41 : How To Find Conflicting Viewpoints In Earth And Space Sciences

Scientist 1: This scientist asserts that drilling for oil should be performed in the ocean. Scientist 1 claims that in the ocean, the oil is at a shorter depth below the Earth’s surface than on dry land. The shorter drilling depth is more ideal for access by drills.

Scientist 2: Scientist 2 believes that drilling for oil should be performed on dry land and not underwater. This is due to the fact that water is at a higher pressure than is observed on the surface of Earth. Scientist 2 asserts that drilling at the lower pressure will be less likely to damage the equipment resulting in an unsuccessful event.

Experiment: The scientists conduct various experiments. The data that the scientists collect indicates the depth at which it is necessary to drill on land and in the ocean in order to reach. The other data that the scientist collect is on the pressure that the equipment will need to experience while drilling for oil at each location.

If the water pressure is greater than the pressure that the drilling equipment can handle, which scientist's viewpoint is strengthened? 

Possible Answers:

Cannot be determined from the given information

Scientist 1, because the pressure is so great on land that the equipment will be damaged

Scientist 2, because there is no water pressure on land, so the equipment will not be damaged

Scientist 1, because there is no water pressure on land so the equipment will not be damaged

Scientist 2, because the pressure is so great on land that the equipment will be damaged

Correct answer:

Scientist 2, because there is no water pressure on land, so the equipment will not be damaged

Explanation:

If the water pressure is higher than the what the equipment can withstand, the equipment will be damaged. It is not desired to damage equipment so the drilling should be done on land, which supports Scientist 2's viewpoint. 

Example Question #41 : Earth And Space Sciences

Scientist 1: This scientist asserts that drilling for oil should be performed in the ocean. Scientist 1 claims that in the ocean, the oil is at a shorter depth below the Earth’s surface than on dry land. The shorter drilling depth is more ideal for access by drills.

Scientist 2: Scientist 2 believes that drilling for oil should be performed on dry land and not underwater. This is due to the fact that water is at a higher pressure than is observed on the surface of Earth. Scientist 2 asserts that drilling at the lower pressure will be less likely to damage the equipment resulting in an unsuccessful event.

Experiment: The scientists conduct various experiments. The data that the scientists collect indicates the depth at which it is necessary to drill on land and in the ocean in order to reach. The other data that the scientist collect is on the pressure that the equipment will need to experience while drilling for oil at each location.

If the equipment can handle the pressure underwater and it is discovered that the depth of oil is the same underwater and on land, which scientist's viewpoint is strengthened? 

Possible Answers:

Scientist 1, because it is less expensive to drill underwater

Cannot be determined form the given information 

Scientist 2, because it is easier to transport oil on land than from a water site

Scientist 1, because it is easier to drill underwater

Scientist 2, because it is easier to drill on land

Correct answer:

Cannot be determined form the given information 

Explanation:

The scientists are only measuring the depth of the oil and the pressure that the equipment can withstand. If the equipment can handle the water pressure and the depth to the oil is the same, there is no way of distinguishing between the two sites. It is not possible to determine whose viewpoint is strengthened. 

Example Question #41 : Earth And Space Sciences

Scientist 1: Scientist 1 claims that the best spot to find gold is near volcanic areas. This scientist claims that the high temperatures and high pressure helps to form the gold. Therefore the best area to find large quantities of gold is near volcanoes.

Scientist 2: Scientist 2 asserts that the best area to find gold is in rivers. In the rivers the gold can be free flowing and easier to see. In addition, the gold found in the rivers does not necessarily require equipment for digging. It is is found in the river due to the water carrying, rather than eroding it. 

Which location would both scientists agree to search for gold at? 

Possible Answers:

A highly active volcanic area 

An area with a bunch of rivers

The scientists will not agree on a location

Cannot be determined from the given information 

River beds located downhill from volcanoes 

Correct answer:

River beds located downhill from volcanoes 

Explanation:

The scientists will most likely agree to search for gold in the river beds by volcanic areas. This area has the benefits of being located near a volcano and also being near rivers that both scientist prefer. 

Example Question #984 : Act Science

Scientist 1: Scientist 1 claims that the best spot to find gold is near volcanic areas. This scientist claims that the high temperatures and high pressure helps to form the gold. Therefore the best area to find large quantities of gold is near volcanoes.

Scientist 2: Scientist 2 asserts that the best area to find gold is in rivers. In the rivers the gold can be free flowing and easier to see. In addition, the gold found in the rivers does not necessarily require equipment for digging. It is is found in the river due to the water carrying, rather than eroding it. 

Which scientist's viewpoint would be weakened if it was discovered that fool's gold is abundant in rivers? 

Possible Answers:

Scientist 1, because it would require more sorting in rivers to determine what is gold

Scientist 2, because it would require more sorting in volcanic areas to determine what is gold

Scientist 2, because it would require more sorting in rivers to determine what is gold

Cannot be determined from the given information

Scientist 1, because it would require more sorting in volcanic areas to determine what is gold

Correct answer:

Scientist 2, because it would require more sorting in rivers to determine what is gold

Explanation:

If there was a lot of fools gold in rivers, this would not be desirable as the scientists are looking for real gold. This would require extra sorting of the gold found to determine what is actually gold and what is not. Scientist 2 was to search for gold in rivers, so Scientist 2's viewpoint would be weakened. 

Learning Tools by Varsity Tutors