Name: 

Passage 1
In the pole vault, the pole acts to convert the energy generated by an athlete running down arunway into a force that lifts the athlete over a crossbar. The most advanced vaulters use stiff poles that quickly convert the horizontal energy into the lifting force. Beginning vaulters are not strong, fast, or skillful enough to bend a stiff pole as needed to generate substantial vertical lift. Beginning vaulters must use more flexible poles.
To test the suitability of two materials for use in poles, scientists subjected three miniature poles to two laboratory tests. Pole No. 1, made of fiberglass, is 50 cm long, with a diameter of 1 cm and amass of 1 kg. Pole No. 2, also made of fiberglass, is also 50 cm long but has a diameter of 1.5 cm and amass of 2.25 kg. Pole No. 3, made of carbon fiber, is 50 cm long, 1.5 cm in diameter, and has a mass of 1kg.

Study 1
Scientists tested the three poles to determine how much force is required to bend the poles to an 85-degree angle. Table 1 shows the results.
Study 2
Scientists bent each pole to an 85-degree angle and then allowed the pole to snap back to a straight position. Table 2 shows the time required for each pole to snap back.

According to the results, what is the relationship between the force required to bend a pole and the time needed for the pole to snap back to its regular position?

On the basis of Study 1, what is the relationship between pole mass and stiffness?

Which of the following is a controlled variable in this study?

Kinetic energy results from the actual motion of an object, while potential energy is a measure of the energy that results if an object moves from a certain location. During a pole vault, at which times is virtually all the energy in the form of potential energy?

Ideally, vaulters like to use long poles becaus the poles reach closer to the crossbar. If a pole is too long, though, a vaulter has difficulty carrying it down the runway because of its mass. Given these considerations, which material is best suited for a very long pole?

On the basis of the entire study, which poles, if they were proportionately enlarged for use by a vaulter, are most appropriate for a beginning and experienced vaulter, respectively?

Passage 2
Very few humans live to the age of 100. Another way of saying this is that almost all members of the human population who were born in a given year will die within 100 years. Scientists, health professionals, and life insurance agents are interested in examining how many people in a population will live to be a certain age. One way to measure this information is to look at how much of the population has died after a certain number of years. This information is presented in Figure 1.

According to Figure 1, approximately what percentage of the human population lives to at least 80 years of age?

The increase in percentage of deaths is highest for which of the following intervals?

Suppose infant mortality (children dying at birth or very shortly thereafter) is eliminated. How will the graph change?

According to the graph, by what age do the largest number of people die?

For a person born the same year this population started, what is the maximum number of years he could live and still observe an 80 percent chance of still being alive?

Passage 3
A radioactive substance is one that contains atoms whose nuclei change into other types of atomic nuclei. For example, a uranium nucleus can lose two protons and two neutrons and become a thorium nucleus. Atoms of some radioactive substances change more frequently than others. Over time, the rate of change for any substance slows as a greater percentage of atomic nuclei change to a final, more stable state.
Devices can measure the number of atomic changes that take place at a given time. Each of these changes is commonly called a disintegration Table 1 and Table 2 show the disintegration rates for two unknown substances.

About how many millicuries will be measured from Substance B after 20 hours?

If Substance A originally had 10,000,000 radioactive atoms, how many atoms are present at 15 hours?

When is the disintegration rate of Substance B 1,500 millicuries?

The half-life of a radioactive substance is the time it takes for half of the radioactive atoms to disintegrate. Which substance has a shorter half-life?

Radioactive substances are potential health hazards. The particles emitted from radioactive substances can damage parts of the human body. Humans should take great care to limit the amount of radioactivity to which they are exposed. Which of the following is safest for a human to handle?

Passage 4
When sunlight heats the earth’s surface, much of that energy is radiated back to the atmosphere.Although some of this re-radiated energy escapes to space, a significant amount of it is reflected back tothe earth’s surface by molecules in the atmosphere. These molecules -- water, nitrous oxide, methane, and carbon dioxide —- trap re-radiated energy as glass in a greenhouse does and warm the earth.Hence, the term “greenhouse effect” has been used to refer to the warming of the earth caused by the gases’ keeping heat within the earth’s atmosphere.
Scientists agree that the greenhouse effect results in higher temperatures on earth but disagreeas to whether recent increases in atmospheric carbon dioxide will lead to undesirable global warming. Two scientists discuss this possibility.
Scientist 1
Ancient ice cores from Antarctica indicate that the concentration of carbon dioxide in the atmosphere and global mean temperatures have followed the same pattern of fluctuations in levels over the past 160,000 years. Therefore, the increase in atmospheric carbon dioxide concentration from 280 parts per million to 360 parts per million that has occurred over the past 150 years points to significant and detrimental climatic changes in the near future. The climate has already changed: the average surface temperature of the earth has increased 0.6°C in the past hundred years, with the ten hottest years of that time period all occurring since 1980. Although 0.6°C may not seem large, changes in the mean surface temperature as low as 0.5°C have dramatically affected crop growth in years past. Moreover, computer models project that surface temperatures will increase about 2.0°C by the year 2100 and will continue to increase in the years after even if concentration of greenhouse gases is stabilized by that time. If the present trend in carbon dioxide increase continues, though,carbon dioxide concentration will exceed 1,100 parts per million soon after 2100 and will be associated with a temperature increase of approximately 10.0°C over the present mean annual global surface temperature.
Scientist 2
The observed increases in minor greenhouse gases such as carbon dioxide and methane will not lead to sizeable global warming. Water vapor and clouds are responsible for more than 98% of the earth’s greenhouse effect. Current models that project large temperature increases with a doubling of the present carbon dioxide concentration incorporate changes in water vapor, clouds, and other factors that would accompany a rise in carbon dioxide levels. The way these models handle such feedbackfactors is not supported by current scientific knowledge. ln fact, there is convincing evidence that increases in carbon dioxide concentration would lead to changes in feedback factors that would diminish any temperature increase associated with more carbon dioxide in the atmosphere. The climatic data for the past hundred years show an irregular pattern in which many of the greatest jumps in global mean temperature were too large to be associated with the observed increase in carbon dioxide. The overall increase of 0.45°C in the past century is well under what the models would have predicted given the changes in carbon dioxide concentration. As with the temperature models, recent increases in atmospheric carbon dioxide have not risen to the extent predicted by models dealing solely with carbon dioxide levels. The rate of carbon dioxide concentration increase has slowed since 1973. Improved energy technologies will further dampen the increase so that the carbon dioxide concentration will be under 700 parts per million in the year 2100.

Which of the following is an assumption madeby Scientist 1?

A scientific article stated that “Scientists will soon develop computer models that accurately account for feedback factors.” Which of the scientists’ viewpoints, if any, is(are) consistent with this statement?

Which of the following is the most likely reason that the two scientists present different figures for the temperature rise that has occurred over the past hundred years?

Indicative of rising temperatures, a large block of the Larson B Ice Sheet in Antarctica recently broke off, raising water levels around the world and increasing the vulnerability of coastal areas to flooding. In light of this information, which of the following predictions would be most consistent with Scientist 1’s viewpoint?

Scientists l and 2 would most likely agree with which of the following statements about atmospheric carbon dioxide levels?

The manner in which Scientist l presents her claim about the significance of increased global temperatures over the past hundred years is most vulnerable to which of the following criticisms?

Scientist 2 implies the truth of which of the following statements?