ACT Science : How to find conflicting viewpoints in earth and space sciences

Study concepts, example questions & explanations for ACT Science

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

Example Questions

← Previous 1 3 4 5 6

Example Question #1 : How To Find Conflicting Viewpoints In Earth And Space Sciences

Since the early 1900s, there has been a steady increase in the earth’s atmospheric temperature, resulting in a phenomenon called “Global Warming.” While the steady temperature change has been well documented, the cause of global warming remains controversial.

Scientist 1

Scientist 1 believes that “external forcings” are the cause of increased temperature over the past century. “External forcings” can direct the change in temperature over thousands of years. One example of an external force is variation in the earth’s orbit around the sun. The earth orbital cycle lasts 26,000 years and causes general trends in warming and cooling.

Scientist 2

Scientist 2 believes that global warming is a man-made phenomenon due to an increase in greenhouse gases such as carbon dioxide or methane. Greenhouse gases have a natural warming effect, however, an increase in the amount of atmospheric greenhouse gases many enhance that effect. Since 1750, the concentration of carbon dioxide has increased 36 percent while the amount of atmospheric methane has increased 148 percent.

Summarize the differences between the scientists' theories.

Possible Answers:

Scientist 1 does not believe there has been a significant change in global temperatures while scientist 2 does.

Scientist 1 believes a global cooling cycle will occur soon while Scientist 2 does not.

Scientist 1 thinks global warming is a naturally occurring phenomenon while Scientist 2 believes man is responsible.

Scientist 1 believes there is no harm in global warming while Scientist 2 believes global warming will be catastrophic.

Correct answer:

Scientist 1 thinks global warming is a naturally occurring phenomenon while Scientist 2 believes man is responsible.

Explanation:

Both scientists acknowledge that global warming has occurred over the past century, however, scientist 1 believes global warming is a natural part of the earth's orbital variances while scientist 2 believes that man has contributed to the increase in temperatures.

Example Question #1 : Earth And Space Sciences

Since the early 1900s, there has been a steady increase in the earth’s atmospheric temperature, resulting in a phenomenon called “Global Warming.” While the steady temperature change has been well documented, the cause of global warming remains controversial.

Scientist 1

Scientist 1 believes that “external forcings” are the cause of increased temperature over the past century. “External forcings” can direct the change in temperature over thousands of years. One example of an external force is variation in the earth’s orbit around the sun. The earth orbital cycle lasts 26,000 years and causes general trends in warming and cooling.

Scientist 2

Scientist 2 believes that global warming is a man-made phenomenon due to an increase in greenhouse gases such as carbon dioxide or methane. Greenhouse gases have a natural warming effect, however, an increase in the amount of atmospheric greenhouse gases many enhance that effect. Since 1750, the concentration of carbon dioxide has increased 36 percent while the amount of atmospheric methane has increased 148 percent.

What data would support Scientist 1's theory?

Possible Answers:

A diagram of the earth's orbital variances

A chart depicting the average atmospheric temperature every 100 years for the past 50,000 years

A chart depicting the average atmospheric temperature each year for the past century

A chart depicting the number of minutes of daylight experienced at a particular location on June 21st each year

Correct answer:

A chart depicting the average atmospheric temperature every 100 years for the past 50,000 years

Explanation:

Because the orbital variance changes so slowly (over thousands of years), it will be necessary to compare the average temperature change over a very long period of time. A diagram depicting the orbital variances may be interesting, however, it is not informative for climate change.

Example Question #2 : How To Find Conflicting Viewpoints In Earth And Space Sciences

Since the early 1900s, there has been a steady increase in the earth’s atmospheric temperature, resulting in a phenomenon called “Global Warming.” While the steady temperature change has been well documented, the cause of global warming remains controversial.

Scientist 1

Scientist 1 believes that “external forcings” are the cause of increased temperature over the past century. “External forcings” can direct the change in temperature over thousands of years. One example of an external force is variation in the earth’s orbit around the sun. The earth orbital cycle lasts 26,000 years and causes general trends in warming and cooling.

Scientist 2

Scientist 2 believes that global warming is a man-made phenomenon due to an increase in greenhouse gases such as carbon dioxide or methane. Greenhouse gases have a natural warming effect, however, an increase in the amount of atmospheric greenhouse gases many enhance that effect. Since 1750, the concentration of carbon dioxide has increased 36 percent while the amount of atmospheric methane has increased 148 percent.

Assume that both Scientist 1 and Scientist 2 were correct. How would temperature change over the next 20,000 years?

Possible Answers:

The average atmospheric temperature will continue to rise at a constant rate.

The temperatures in the summers will be hotter while the temperatures in the winter will be cooler.

The average atmospheric temperature will increase and decrease in a cyclical manner.

There would be an increase in atmospheric temperature, however, the rate of increase would change depending on variances in the earth's orbit.

Correct answer:

There would be an increase in atmospheric temperature, however, the rate of increase would change depending on variances in the earth's orbit.

Explanation:

A situation in which the temperature continues to increase, but the rate of increase is correlated with changes in the earth's orbit suggests that both scientists are correct. A constant increase in temperature suggests Scientist 2 is correct, while increased and decreased temperature suggests that Scientist 1 is correct.

Example Question #4 : How To Find Conflicting Viewpoints In Earth And Space Sciences

According to the Big Bang theory, which proposes that the universe is roughly 13.8 billion years old, all matter and energy were at one time compressed into a single microscopic point. This point then exploded outward in all directions in a rapid expansion. The expansion has continued to the present day, though it has decelerated significantly, which has allowed matter to cool to a state at which stable atomic components can form. The Big Bang theory proposes that our universe is finite in age, and since nothing can travel faster than the speed of light, there exists a cosmological horizon, which is the maximum distance light or energy could have travelled since the occurrence of the Big Bang. Since the universe is still expanding, however, regions of space that are visible from our vantage point are not within each other's cosmological horizons. For example, if galaxy A is 10 billion light years away from us, and galaxy B is 10 billion light years away from us in the opposite direction, there is a total distance of 20 billion light years between them. The universe has only existed long enough for light, energy, or information to travel 13.8 billion light years between them; thus, it is not possible for any contact to have been made between the two galaxies. Yet, even these vastly separated regions of space have been observed to be extremely homogeneous—they have remarkably similar features and properties despite being so far away from each other. The question, therefore, is what caused this apparent homogeneity observed in the universe. If matter rapidly expanded outward, why does the universe have such a uniform appearance in every direction? If the Big Bang theory is correct, some explanation for this horizon problem is needed.

Scientist 1

In the current state of the universe there exist regions that lie beyond the cosmological horizons of others, and therefore cannot possibly be influenced by them. This was not always the case. At a point in time mere microseconds after the Big Bang, all of the matter in the universe experienced a period of exponential expansion, known as inflation, before the rate of expansion fell to a more stable level. This inflation led to all regions of the universe having homogeneous features even though they are not capable of affecting one another in any way in their modern state.

Scientist 2

Although there is ample evidence that a Big Bang occurred, the horizon problem, as well as the flatness problem, suggest that the Big Bang is not the full story of the inception of the universe. The horizon problem can be solved if, instead of viewing the Big Bang as the "beginning of everything," we stipulate that the expansion seen after the Big Bang was already occurring for some time before the Big Bang occurred. This marks the Big Bang as a sort of "causal horizon," which disallows us from directly observing evidence from any period beforehand. If we assume the universe is cyclic, the homogeneity of the universe is explained as the result of a continuous cycle of expansion and compression, which would naturally lead to a universe having uniform features.

If Scientist 1's theory were correct, which of the following would be a worthwhile question for scientists to further study?

Possible Answers:

How could all matter and energy in the universe have been compressed into a single point?

Is it possible to develop methods to gather information about the period of expansion prior to the Big Bang?

What caused the fluctuations in the rate of outward expansion directly after the Big Bang?

How did all the regions of space become homogeneous?

Is it possible for information to travel faster than the speed of light?

Correct answer:

What caused the fluctuations in the rate of outward expansion directly after the Big Bang?

Explanation:

If Scientist 1's theory were correct, that would mean there was a period of rapid expansion following the Big Bang. This assumption naturally leads to the question: "What caused the fluctuations in the rate of outward expansion directly after the Big Bang?"

Scientist 1's theory already provides a reasoning for the homogeneity of the universe and gives an explanation of the Big Bang. Scientist i's theory does not assume a period of expansion prior to the Big Bang, nor does it require information to travel faster than the speed of light.

Example Question #3 : How To Find Conflicting Viewpoints In Earth And Space Sciences

According to the Big Bang theory, which proposes that the universe is roughly 13.8 billion years old, all matter and energy were at one time compressed into a single microscopic point. This point then exploded outward in all directions in a rapid expansion. The expansion has continued to the present day, though it has decelerated significantly, which has allowed matter to cool to a state at which stable atomic components can form. The Big Bang theory proposes that our universe is finite in age, and since nothing can travel faster than the speed of light, there exists a cosmological horizon, which is the maximum distance light or energy could have travelled since the occurrence of the Big Bang. Since the universe is still expanding, however, regions of space that are visible from our vantage point are not within each other's cosmological horizons. For example, if galaxy A is 10 billion light years away from us, and galaxy B is 10 billion light years away from us in the opposite direction, there is a total distance of 20 billion light years between them. The universe has only existed long enough for light, energy, or information to travel 13.8 billion light years between them; thus, it is not possible for any contact to have been made between the two galaxies. Yet, even these vastly separated regions of space have been observed to be extremely homogeneous—they have remarkably similar features and properties despite being so far away from each other. The question, therefore, is what caused this apparent homogeneity observed in the universe. If matter rapidly expanded outward, why does the universe have such a uniform appearance in every direction? If the Big Bang theory is correct, some explanation for this horizon problem is needed.

Scientist 1

In the current state of the universe there exist regions that lie beyond the cosmological horizons of others, and therefore cannot possibly be influenced by them. This was not always the case. At a point in time mere microseconds after the Big Bang, all of the matter in the universe experienced a period of exponential expansion, known as inflation, before the rate of expansion fell to a more stable level. This inflation led to all regions of the universe having homogeneous features even though they are not capable of affecting one another in any way in their modern state.

Scientist 2

Although there is ample evidence that a Big Bang occurred, the horizon problem, as well as the flatness problem, suggest that the Big Bang is not the full story of the inception of the universe. The horizon problem can be solved if, instead of viewing the Big Bang as the "beginning of everything," we stipulate that the expansion seen after the Big Bang was already occurring for some time before the Big Bang occurred. This marks the Big Bang as a sort of "causal horizon," which disallows us from directly observing evidence from any period beforehand. If we assume the universe is cyclic, the homogeneity of the universe is explained as the result of a continuous cycle of expansion and compression, which would naturally lead to a universe having uniform features.

On what grounds might Scientist 1 criticize Scientist 2's theory?

Possible Answers:

It builds on an outdated model of the universe

It does not explain why there was an inflationary period of rapid expansion shortly after the Big Bang

It is untestable, and therefore outside the realm of natural science

It does not actually address the horizon problem

It dismisses the Big Bang theory with no scientific explanation

Correct answer:

It is untestable, and therefore outside the realm of natural science

Explanation:

Scientist 2's theory relies on a theoretical period of expansion before the Big Bang occurred, which would be unobservable from our vantage point. Since no experiment or apparatus could be devised that would be able to prove or disprove this theorized cyclic expansion, the theory is untestable, and untestable theories fall outside the realm of natural science.

All the other answer options either misrepresent Scientist 2's theory or ask it to explain features that were not assumed within that theory.

Example Question #3 : Earth And Space Sciences

According to the Big Bang theory, which proposes that the universe is roughly 13.8 billion years old, all matter and energy were at one time compressed into a single microscopic point. This point then exploded outward in all directions in a rapid expansion. The expansion has continued to the present day, though it has decelerated significantly, which has allowed matter to cool to a state at which stable atomic components can form. The Big Bang theory proposes that our universe is finite in age, and since nothing can travel faster than the speed of light, there exists a cosmological horizon, which is the maximum distance light or energy could have travelled since the occurrence of the Big Bang. Since the universe is still expanding, however, regions of space that are visible from our vantage point are not within each other's cosmological horizons. For example, if galaxy A is 10 billion light years away from us, and galaxy B is 10 billion light years away from us in the opposite direction, there is a total distance of 20 billion light years between them. The universe has only existed long enough for light, energy, or information to travel 13.8 billion light years between them; thus, it is not possible for any contact to have been made between the two galaxies. Yet, even these vastly separated regions of space have been observed to be extremely homogeneous—they have remarkably similar features and properties despite being so far away from each other. The question, therefore, is what caused this apparent homogeneity observed in the universe. If matter rapidly expanded outward, why does the universe have such a uniform appearance in every direction? If the Big Bang theory is correct, some explanation for this horizon problem is needed.

Scientist 1

In the current state of the universe there exist regions that lie beyond the cosmological horizons of others, and therefore cannot possibly be influenced by them. This was not always the case. At a point in time mere microseconds after the Big Bang, all of the matter in the universe experienced a period of exponential expansion, known as inflation, before the rate of expansion fell to a more stable level. This inflation led to all regions of the universe having homogeneous features even though they are not capable of affecting one another in any way in their modern state.

Scientist 2

Although there is ample evidence that a Big Bang occurred, the horizon problem, as well as the flatness problem, suggest that the Big Bang is not the full story of the inception of the universe. The horizon problem can be solved if, instead of viewing the Big Bang as the "beginning of everything," we stipulate that the expansion seen after the Big Bang was already occurring for some time before the Big Bang occurred. This marks the Big Bang as a sort of "causal horizon," which disallows us from directly observing evidence from any period beforehand. If we assume the universe is cyclic, the homogeneity of the universe is explained as the result of a continuous cycle of expansion and compression, which would naturally lead to a universe having uniform features.

Which of the following, if true, would most support Scientist 2's claim?

Possible Answers:

Scientists determine that the universe is actually significantly older than previously stated, allowing a much greater time for information to travel vast distances.

New evidence casts doubt on the homogeneity of far-apart regions of the universe.

New evidence suggests a period of rapid expansion took place shortly after the Big Bang.

New cosmological evidence suggests a period of expansion that began prior to the Big Bang.

Acceptance of the cyclic theory of the universe is more widespread in the scientific community.

Correct answer:

New cosmological evidence suggests a period of expansion that began prior to the Big Bang.

Explanation:

Scientist 2's theory depends upon a view of the universe in which the Big Bang was preceded by other expansion events. The only answer choice that supports this view is the one that states, "New cosmological evidence suggests a period of expansion that began prior to the Big Bang."

Widespread acceptance of a theory does not help provide evidence ot support it. The other answer choices do not support Scientist 2's theory, and in some cases undermine it.

Example Question #3 : How To Find Conflicting Viewpoints In Earth And Space Sciences

The origin of the universe has been a highly debated topic among physicists. In the middle of the twentieth century, there were two prevalent models regarding the origin of the universe. The first model, called the Big Bang Theory, suggests that the universe was spontaneously created approximately 14 billion years ago. The second model, called the Steady State Theory, suggests that the universe contains no beginning or end, is always expanding, and contains a constant density.

Initially, the Big Bang Theory was widely disregarded by physicists and astronomers. In fact, the name “Big Bang” was coined by Fred Hoyle, a supporter of the Steady State Theory, who used the term in a derogatory manner. The Big Bang Theory suggests that prior to the creation of matter, a physical object that occupies space and possesses mass, the universe was filled homogenously with high-energy density and very high temperature and pressure. The universe was rapidly expanding and cooling resulting in the creation of atoms. The initial atoms that were produced were much lighter than the atoms currently found on earth, the lightest of which are hydrogen, helium, and lithium. After this initial creation of the universe, it continued to expand.  The Big Bang Theory is now the prevalent theory for the origin of the universe.

The Steady State Theory suggests that there is no start or end to the universe in time or space, yet the universe is always expanding. Furthermore, the Steady State Theory states that new stars and galaxies replace old stars and galaxies and the overall appearance of the universe does not change over time.

Two sources of evidence are used to support or refute the discussed hypotheses. The first piece of data is the presence of primordial gas clouds, pockets of the universe that contain gases lighter than those found in the current universe. The second piece of evidence is that other galaxies are “red shifted”. The term red-shift indicates that as objects move farther away, the light they emit changes wavelength and appears to be more red.

Which model suggests a greater age of the universe?

Possible Answers:

There is no solution because the Steady State Theory does not propose a finite age to the universe.

There is no solution because supporters of the Big Bang Theory cannot agree on the age of the universe.

Steady State Theory

Big Bang Theory

Correct answer:

There is no solution because the Steady State Theory does not propose a finite age to the universe.

Explanation:

Supporters of the Big Bang Theory agree that the universe originated a little less than 14 billion years ago. However, the Steady State Theory suggests that the universe always existed, however, since that is an abstract time frame, it is impossible to determine if "always existed" is greater than 14 billion years ago.

Example Question #5 : Earth And Space Sciences

The origin of the universe has been a highly debated topic among physicists. In the middle of the twentieth century, there were two prevalent models regarding the origin of the universe. The first model, called the Big Bang Theory, suggests that the universe was spontaneously created approximately 14 billion years ago. The second model, called the Steady State Theory, suggests that the universe contains no beginning or end, is always expanding, and contains a constant density.

Initially, the Big Bang Theory was widely disregarded by physicists and astronomers. In fact, the name “Big Bang” was coined by Fred Hoyle, a supporter of the Steady State Theory, who used the term in a derogatory manner. The Big Bang Theory suggests that prior to the creation of matter, a physical object that occupies space and possesses mass, the universe was filled homogenously with high-energy density and very high temperature and pressure. The universe was rapidly expanding and cooling resulting in the creation of atoms. The initial atoms that were produced were much lighter than the atoms currently found on earth, the lightest of which are hydrogen, helium, and lithium. After this initial creation of the universe, it continued to expand.  The Big Bang Theory is now the prevalent theory for the origin of the universe.

The Steady State Theory suggests that there is no start or end to the universe in time or space, yet the universe is always expanding. Furthermore, the Steady State Theory states that new stars and galaxies replace old stars and galaxies and the overall appearance of the universe does not change over time.

Two sources of evidence are used to support or refute the discussed hypotheses. The first piece of data is the presence of primordial gas clouds, pockets of the universe that contain gases lighter than those found in the current universe. The second piece of evidence is that other galaxies are “red shifted”. The term red-shift indicates that as objects move farther away, the light they emit changes wavelength and appears to be more red.

The red shift of other galaxies supports which theory?

Possible Answers:

Steady State Theory

Both theories

Big Bang Theory

Correct answer:

Both theories

Explanation:

The red shift of other galaxies indicates that they are moving farther away and that the universe is expanding. An expanding universe is a component of both theories, therefore, this phenomenon supports both.

Example Question #5 : How To Find Conflicting Viewpoints In Earth And Space Sciences

The origin of the universe has been a highly debated topic among physicists. In the middle of the twentieth century, there were two prevalent models regarding the origin of the universe. The first model, called the Big Bang Theory, suggests that the universe was spontaneously created approximately 14 billion years ago. The second model, called the Steady State Theory, suggests that the universe contains no beginning or end, is always expanding, and contains a constant density.

Initially, the Big Bang Theory was widely disregarded by physicists and astronomers. In fact, the name “Big Bang” was coined by Fred Hoyle, a supporter of the Steady State Theory, who used the term in a derogatory manner. The Big Bang Theory suggests that prior to the creation of matter, a physical object that occupies space and possesses mass, the universe was filled homogenously with high-energy density and very high temperature and pressure. The universe was rapidly expanding and cooling resulting in the creation of atoms. The initial atoms that were produced were much lighter than the atoms currently found on earth, the lightest of which are hydrogen, helium, and lithium. After this initial creation of the universe, it continued to expand.  The Big Bang Theory is now the prevalent theory for the origin of the universe.

The Steady State Theory suggests that there is no start or end to the universe in time or space, yet the universe is always expanding. Furthermore, the Steady State Theory states that new stars and galaxies replace old stars and galaxies and the overall appearance of the universe does not change over time.

Two sources of evidence are used to support or refute the discussed hypotheses. The first piece of data is the presence of primordial gas clouds, pockets of the universe that contain gases lighter than those found in the current universe. The second piece of evidence is that other galaxies are “red shifted”. The term red-shift indicates that as objects move farther away, the light they emit changes wavelength and appears to be more red.

The discovery of primordial gas clouds supports which theory?

Possible Answers:

Steady State Theory

Big Bang Theory

Neither theory

Both theories

Correct answer:

Big Bang Theory

Explanation:

The steady state theory indicates that all parts of the universe look identical. The primordial clouds have an "older" appearance refuting that component of the steady state theory. The Big Bang Theory states that the modern universe was created by an older universe. The presence of the primordial clouds gives credibility to the theory since the gases found there have a smaller mass than those on earth. In fact, the observation of the primordial clouds was one of the recent solid pieces of evidence in support of the Big Bang Theory.

Example Question #7 : Earth And Space Sciences

Global warming is defined as the slow increase in the temperature of the earth’s atmosphere and is caused by pollutants and carbon dioxide (CO2). While the gradual increase in temperature cannot be refuted, scientists argue over the cause.

 Scientist 1:

Global warming is caused by increases in atmospheric CO2, which is directly created by humans and their consumption of fossil fuels. The natural CO2 released from carbon sinks has a different isotopic ratio from the CO2 released from fossil fuels. Current measurements of the radioactive isotopes of CO2 show that it is from human activity, not from nature. The Earth’s carbon sinks cannot absorb these large amounts of unnatural CO2 emissions. About fifty percent of the CO2 produced by mankind remains in the atmosphere, unable to be absorbed.

Scientist 2:

The rise in atmospheric CO2 levels are a result of global warming, not the cause of it. When the temperature increases, the CO2 in carbon sinks is released. While humans do cause release of CO2, the carbon sinks absorb it. The activity of the carbon sinks increases to allow for higher levels of CO2 absorption. Proponents for human causation of global warming point to the warming and cooling of the stratosphere, however, these temperature fluctuations are caused by changes in the sun’s heat. These proponents also look at the acidity of the ocean as evidence of human causation, however, the rise in ocean acidity is within the normal range of fluctuations over the past ten thousand years.

The main beliefs of each scientist can best be described by which of the following statements?

Possible Answers:

Scientist 2 does not believe that global warming exists.

Scientist 2 believes in human causation of global warming, while Scientist 1 does not.

Neither Scientist 1, nor Scientist 2 believes in human causation of global warming.

Scientist 2 does not believe that global warming exists, while Scientist 1 believes global warming is caused by humans.

Scientist 1 believes in human causation of global warming, while Scientist 2 does not.

Correct answer:

Scientist 1 believes in human causation of global warming, while Scientist 2 does not.

Explanation:

Scientist 1 believes that the CO2 released from human use is most causal in contributing to global warming. He goes into detail about the different CO2 isotopes to support his theory. Scientist 2 believes that the increase in CO2 levels is due to global warming, not the cause of it. Scientist 2 supports this by stating that the carbon sinks are able to absorb the excessive CO2 created by humans. Both scientists agree that global warming exists.

← Previous 1 3 4 5 6
Learning Tools by Varsity Tutors

Incompatible Browser

Please upgrade or download one of the following browsers to use Instant Tutoring: