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Example Question #101 : 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.
What new evidence would support the argument made by Scientist 2?
Evidence showing the release of CO2 from carbon sinks directly increases the atmospheric temperature
Evidence showing that temperature increase predated the release of CO2 from carbon sinks
A studying showing that carbon sinks can only absorb a finite amount of CO2
An experiment suggesting that 83% of CO2 remaining in the atmosphere is caused by humans
Evidence showing temperature fluctuations cause the sun's heat to increase in intensity
Evidence showing that temperature increase predated the release of CO2 from carbon sinks
Evidence showing that temperature increase predated the release of CO2 from carbon sinks would support the theory of Scientist 2. Scientist 2 argues that the rising temperature led to an increase in atmospheric CO2, rather than CO2 leading to an increase in temperature. An increase in temperature before an increase in CO2 would be consistent with this reasoning.
Example Question #1 : How To Find Research Summary 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 Steady State Theory states:
The universe originated from light
All of the other choices
The universe was created 14 billion years ago
The overall appearance of the universe does not change
The overall appearance of the universe does not change
The Steady State theory claims the the universe has always existed in time and space and that its overall appearance does not change. This indicates that things may be created and destroyed, but new and old galaxies will appear identical.
Example Question #1 : How To Find Research Summary 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.
A primordial gas has less mass than ________.
Hydrogen
An atom
Light
Energy
Hydrogen
The primoridal gases at the creation of the universe contained less mass than the elements on earth today. Hydrogen is the smallest element, therefore, primordial gases must comprise less mass than hydrogen. Atoms can vary in size and mass based on the type. Energy and light do not contain mass.
Example Question #1 : How To Find Research Summary 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.
A red-shift can be used to estimate_________.
The size of the universe
The intensity of light
Whether an object is moving away.
Color
Whether an object is moving away.
From the text: The term red-shift indicates that as objects move farther away, the light they emit changes wavelength and appears to be more red.
Therefore, an object that has a red-shift is moving farther away from the observer. This phenomenon can be used to determine if galaxies are moving farther away.
Example Question #2 : How To Find Research Summary 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 word is defined as an object that contains mass and occupies space?
Universe
Light
Matter
Energy
Matter
The definition was provided in the text: The Big Bang Theory suggests that "prior to creation of matter, a physical object that occupies space and possesses mass . . ."
Example Question #1 : How To Find Research Summary In Earth And Space Sciences
A scientist observes the motion of stars, planets, and other objects in deep space through a high-powered telescope. She observes that these objects all appear to be moving away from the Earth and graphs her results comparing their velocities, in kilometers per second, and their proper distance, in megaparsecs.
Based on this graph, which of the following conclusions is valid?
Objects in deep space slow down as they reach greater pockets of emptiness.
No valid conclusion can be drawn.
The velocity of an object in deep space and its distance from Earth are proportional.
The velocity of an object in space is independent on its distance.
The velocity of an object in deep space and its distance from Earth are proportional.
Based upon the graph, the farther away the object is, the higher it's velocity away from the earth. Since the graph is linear, then the two are proportional.
Example Question #2 : How To Find Research Summary In Earth And Space Sciences
A scientist observes the motion of stars, planets, and other objects in deep space through a high-powered telescope. She observes that these objects all appear to be moving away from the Earth and graphs her results comparing their velocities, in kilometers per second, and their proper distance, in megaparsecs.
Which one of the following statements, if true, best supports the findings of this experiment?
The universe is ever-expanding.
All distance can be measured in a linear fashion.
None of these statements support the findings.
The universe has a closed volume and these distant objects are at the end of it.
The universe is ever-expanding.
The best solution is that the universe is ever-expanding. While our given graph does not expand infinitely, the line will extend infinitely -- we can extrapolate the velocity of an object of any distance away from the Earth. We can do so up to infinity, thus leading to the conclusion that the universe is ever-expanding.
Example Question #1 : How To Find Research Summary In Earth And Space Sciences
A scientist observes the motion of stars, planets, and other objects in deep space through a high-powered telescope. She observes that these objects all appear to be moving away from the Earth and graphs her results comparing their velocities, in kilometers per second, and their proper distance, in megaparsecs.
A new star is observed. Which of the following pieces of information is necessary to find out how far away it is?
The mass of the star.
The frequency it twinkles.
How quickly it is moving away.
The color of the star.
How quickly it is moving away.
The only thing we need in order to use this graph is the velocity of the star. If we can find the velocity, we can find the distance.
Example Question #3 : How To Find Research Summary In 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.
Scientist 1 uses which of the following as evidence towards human causation of global warming?
When temperature increases, the CO2 in the carbon sinks is released.
While humans do cause releases of CO2, the carbon sinks absorb it.
The Earth’s carbon sinks cannot absorb large amounts of natural CO2 emissions.
Natural CO2 released from carbon sinks has the same isotopic ratio from the CO2 released from fossil fuels.
Natural CO2 released from carbon sinks has a different isotopic ratio from the CO2 released from fossil fuels.
Natural CO2 released from carbon sinks has a different isotopic ratio from the CO2 released from fossil fuels.
Scientist 1 suggests that 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.
Example Question #1 : How To Find Research Summary In Earth And Space Sciences
Scientists have long debated the origin of organic molecules on Earth. Organic molecules are those based on the atom carbon, which can form four distinct bonds in contrast to the fewer number allowed in most other non-metals. As a result of this property, carbon can give rise to the enormously complex molecular shapes necessary for life to arise.
Some scientists argue that organic matter was dissolved in water ice on comets, and brought to Earth early in its history. These comets crashed into the early Earth, and deposited carbon-based molecules in copious quantities to the Earth’s surface as their water melted.
In 2014, the first space probe landed on the comet 67P/Churyumov-Gerasimenko. Suppose that scientists find the following information from 5 distinct samples after landing on the comet. Each sample was taken at a single geographical location, but 5 meters deeper than the last. Sample 1 was taken at a depth of 1 meter below the surface.
Sample # |
Water Ice? |
Concentration of Organics |
1 |
No |
N/A |
2 |
Yes |
1 mg/L |
3 |
No |
N/A |
4 |
Yes |
4 mg/L |
5 |
Yes |
10 mg/L |
These samples were compared to 5 similar samples from the surface of Mars. Scientists posited that this comparison would be meaningful because we know that life does not exist on Mars the same way that it does on Earth. Thus, they are comparing a known non-biological celestial body, Mars, with another celestial body, the comet, which may be seeding life on suitable plants.
Sample # |
Water Ice? |
Concentration of Organics |
1 |
No |
N/A |
2 |
No |
N/A |
3 |
No |
N/A |
4 |
No |
N/A |
5 |
Yes |
1 mg/L |
Which of the following facts would be most supportive of the suggestion that comets seeded organic molecules on Earth before life first developed?
Comet strikes were very common early in the Earth's history, but have become less common.
Few comets contain organic molecules at such high concentrations as 67P/Churyumov-Gerasimenko.
Comet strikes were very rare, but have been more common in more recent Earth history
Most organic molecules are vaporized before comets land on the Earth
Comet strikes were never common in the Earth's history
Comet strikes were very common early in the Earth's history, but have become less common.
The concept of seeding organic molecules to help jump start the evolution of life on Earth demands that early comet strikes took place. Thus, the early, frequent collisions of organics-rich comets with the Earth would be most consistent with this hypothesis.
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