Physics - Unit 1 Test
Which of the following values is equal to 1 micrometer?
0.000001 meter
This direct relationship graph shows that the position of the car ______ as time elapses.
X moving
Around 1910, Rutherford bombarded gold foil with alpha particles. Most of the alpha particles passed straight through. To his surprise, a smaller number were deflected by 180°. This summary recounts the scientific discovery of
something that deflects alpha particles.
A space shuttle was launched from the Earth to the moon. The average, or accepted, value of the distance of the Earth to the moon is 238,857 miles, but the shuttle crew recorded that their trip took 226,316 miles. Calculate the percent error of the distance to the moon.
5.25%
What does this graph show about the relationship between mass and acceleration?
As mass increases, acceleration decreases.
Graphs and tables are two ways that scientists can ______ data.
analyze
Mr. Nakamora wants to test the accuracy of an old balance in his classroom compared to a brand-new balance that he knows is accurate. He weighs an object on the old balance and finds it to have a mass of 15.6 grams. The same object weighs 15.9 grams on the brand-new balance. What is the percent error between the old and new balance?
1.89%
Noted scientist Dr. Elsa Birde described the effect of adding a mixture of dried apples and raisins to the previous feed of sunflower seeds, millet, thistle seed, and cracked corn in bird feeders in her yard. Over three years, Dr. Birde observed that the new mixture increased the number of songbirds at her feeders, especially during the months of April and May. As she has done for several years, Dr. Birde recorded, at the same time each day, the number of birds at each of her four feeders. She noted that the third year using the mixture coincided with the largest increase. There was a twenty-five percent increase in the number of songbirds over times when this mixture was not used. Dr. Birde also noted that in the third year she used a specific ratio of the ingredients, carefully measuring, which she had not done in previous years. The third year also had a warmer than normal spring, and a construction project began in a neighborhood near Dr. Birde's. Dr. Birde is now going to produce this formula for sale and advertise to customers that they may see the same twenty-five percent increase in songbirds at their feeders. Dr. E. Birde, Journal of Scientific Bird Feeding Which scientific claim can be made?
A study by Dr. Birde showed that the number of songbirds in her yard increased due to a modified food source.
In what way would a digital thermometer be preferable to those from a liquid-based thermometer?
Digital thermometer readings can be more readily combined with computer software.
Which expression should appear in the blue box to compute percent error?
Experimental value - Accepted value
Which most likely is a causal relationship?
Experimenters show a link between adult-onset diabetes and obesity.
What statements best define percent error?
It is a mathematical way of showing accuracy. The higher the percent error, the less accurate the data set. A percent error always has a positive value.
Which hypothesis could be used in a scientific experiment and possibly lead to more hypotheses and experimentation?
If students spend more time reading on their own, their ELA grades will increase, because they will have more practice analyzing what they read.
The Global Youth Tobacco Survey asks youth to fill in the answers to several questions about their tobacco use. In this survey conducted between 2000 and 2007, it was found that in youth ages 13-15, 12 percent of boys and 7 percent of girls reported smoking cigarettes. This information was shared and reported on the American Cancer Society website. The information was then used by several industries in the fields of health care, insurance, and education. What is a reason that these data may be unreliable?
It is from a self-reporting survey, and teens may not want to answer the questions honestly.
In the seventeenth century, Robert Hooke conducted many experiments with springs. In all the data he recorded, he found that the force needed to push down on a spring or stretch it out from its usual resting point was equal to the spring's stiffness multiplied by the distance it is pushed or pulled from its resting point. He wrote the equation F = kX, in which F is the force, k is the spring's stiffness, and X is the distance the end of the spring moves from its usual resting point when no push or pull is applied. The equation is still used today. Which best describes Hooke's equation?
It is a law, because it states how force relates to a spring but does not explain why.
Which statements describe scientific laws but not theories or hypotheses?
They do not provide explanations for why they are true. They are considered to be proven facts.
A lightweight material is being tested for effectiveness in blocking ultraviolet (UV) rays from the sun that cause skin to burn and possibly develop skin cancer. Which method would be most helpful for testing this material?
Test the material in controlled natural settings by using natural UV light, and measure the UV light that passes through.
Which statement best describes the variables in a controlled experiment?
The independent variable is changed to see its effect on the dependent variable while all other conditions are unchanged.
In a lesson about the behavior of gases, Genaris and her classmates learn that the volume of a gas is affected by its temperature. They formulated a hypothesis: If the temperature of a gas increases, the volume of the gas will increase because the increased temperature will increase the kinetic energy of the particles, which will then result in the expansion of the gas. The results of their experiment supported the hypothesis. They wanted to know if there were other factors that affect the volume of a gas. What would Genaris and her classmates most likely do to test this idea?
They would formulate a new hypothesis with the same dependent variable but a different independent variable as the original hypothesis.
Which statements correctly describe theories?
X All theories that scientists could discover have already been written. Parts of theories cannot be disproved, but new parts can be added. Theories and laws are the same types of rules about how nature works.
What type of relationship occurs when two variables both increase or decrease together?
a direct relationship
Which type of scientific statement describes a proven fact about how things function in nature?
a law
What must be part of a quantitative observation?
a number
Silus wants to monitor the temperature of a reaction every 0.5 seconds for 30 minutes. He plans to generate a graph of the temperature values over time and insert the graph into a text document. Which pair of tools would be best for Silus to use?
an electronic temperature probe and a computer
For a final project in Seon's physics class, students were instructed to build a water balloon launcher, write a hypothesis, and then carry out an experiment with the launcher. Considering that 90 degrees means launching the balloon straight up into the air and 0 degrees means launching it straight along the ground, Seon first wrote the hypothesis below. If the angle at which the balloon is launched decreases from 90 degrees, then the distance that the balloon goes along the ground will increase, because more energy will go into pushing the balloon forward than upward. Seon found that this was true until the angle reached about 45 degrees, and then the distance along the ground began to decrease again. Seon knows that he will need to write a new explanation, but he would like to conduct an experiment that is based on his original hypothesis, with one of the variables changed. How could Seon rewrite his hypothesis to be a statement that will more likely be supported?
change the independent variable to "If the angle at which the balloon is launched moves closer to 45 degrees . . ."
An experiment was conducted to see which metal pot would be better for cooking food quickly. The table below shows how quickly small pieces of wax melted during the experiment. The following statement was made after the data were examined: "Copper pots are the best pots for cooking food quickly." Which term best describes this statement?
conclusion
Which is an example of making a qualitative observation?
describing how copper changes color in chlorine
Which is one way that scientists communicate the results of an experiment?
drawing a picture
Some studies has shown that peppermint odor increases people's mental sharpness, especially when they solve math problems. Which best describes how this could be a valid scientific claim?
if it is tested in a controlled setting with repeated results
Several scientists from different countries are asked to examine the results of an experiment before a journal will print it. Which term best describes this step of the investigative process?
peer review
The theory of global warming states that the average temperature of the earth has been increasing over time. This theory will be most strongly affected by scientific studies that
reveal how the earth's temperature has fluctuated in the past.
Which factor is found in a scientific claim?
similar results in multiple tests of the claim
Which trait would most likely lead a scientist to repeat an experiment and verify the data?
skepticism
Knowledge of atomic structure has evolved over time. Thomson discovered that atoms contain electrons, Rutherford discovered that most of the mass of an atom is concentrated in its center, and Bohr discovered that electrons orbit the nucleus. Taken together, what do these discoveries demonstrate?
the cumulative nature of science
Dalton was an English schoolteacher, Rutherford was a chemist from New Zealand, and Bohr was a Danish physicist. Each made important contributions to the atomic model. Taken together, what do these scientists demonstrate?
the importance of diversity in the growth of scientific knowledge
From the ancient Greeks to more recent times, scientists saw the brain as a "blank slate," meaning that it is completely blank at birth and anything can be written onto it. However, as studies of genetics and evolution expanded throughout the twentieth century, scientists found more evidence that many of our behaviors and thoughts are determined by genetics long before a child is born. Therefore, the understanding of human thinking has moved away from the "blank slate" because the explanation that thoughts and behaviors are a mix of what humans are born with and what humans learn better fits experimental results and observations. The decline of scientists' acceptance of the "blank slate" idea is an example of how a(n) ______ can change to better fit evidence.
theory
Which best describes the purpose of a control sample?
to compare its results to those with the experimental sample
What is a caliper used for?
to make a precise measurement of length
The independent variable is typically placed on the ___ -axis of a graph.
x
Which of these units is most appropriate to use when measuring the mass of a person?
kilogram
Which of these units is most appropriate for describing a 26-mile marathon run?
kilometer
Which is an example of making a quantitative observation?
measuring the mass of metal used in a reaction
Which scientists contributed to the determination of how CFCs in clouds in the upper atmosphere could destroy ozone molecules?
meteorologists and chemists
Ricardo wants to determine the length of a strip of zinc metal. What is the SI unit for length?
meter
A group of scientists have obtained some experimental results. How would the group best find out whether their study is worth more time and resources?
by presenting the results in a poster session
Which is part of a proper graph?
consistent intervals on each axis
A biochemist performs an experiment to study the behavior of water molecules near proteins. He concludes that water molecules occur in groups of five in the presence of proteins. Skepticism is important in this scenario because it would help him to
ensure that his conclusion is supported by evidence.
Knowledge of the structure of a pesticide is important because it affects the
explanation of why the pesticide is toxic to organisms.
A science class tested ways to clean water after an oil spill. Each group of students was given 100 mL of vegetable oil, 100 mL of engine oil, and 800 mL of water in a rectangular plastic container. Each container also held five floating wooden cubes (5 cubic centimeters each) representing animals in the water. Each group was tasked with removing as much oil as possible in a 20 minute period, leaving "clean water" in the container, using whatever tools they brought to class. The results of the "clean-up" are presented in the table below. Based on the results above, which group's data seem unreliable?
group 2
Below is the data from a gas law experiment comparing the pressure and the volume of a gas at a given temperature. Which graph best shows the relationship between pressure and volume?
https://media.edgenuity.com/evresources/8301/8301-01/8301-01-06/8301-01-06-assessment/8301-01-06-08a.png
Gerry and Lena work in a modern physics laboratory and study nanotechnology, which is a new type of technology that allows control over individual particles as small as molecules or atoms. Even though they work with new technology, they still follow the scientific method, so their experiments attempt to find relationships between independent and dependent variables. For each experiment involving nanotechnology, Gerry and Lena will test a(n)
hypothesis
Noted scientist Dr. Elsa Birde described the effect of adding a mixture of dried apples and raisins to the previous feed of sunflower seeds, millet, thistle seed, and cracked corn in bird feeders in her yard. Over three years, Dr. Birde observed that the new mixture increased the number of songbirds at her feeders, especially during the months of April and May. As she has done for several years, Dr. Birde recorded, at the same time each day, the number of birds at each of her four feeders. She noted that the third year using the mixture coincided with the largest increase. There was a twenty-five percent increase in the number of songbirds over times when this mixture was not used. Dr. Birde also noted that in the third year she used a specific ratio of the ingredients, carefully measuring, which she had not done in previous years. The third year also had a warmer than normal spring, and a construction project began in a neighborhood near Dr. Birde's. Dr. Birde is now going to produce this formula for sale and advertise to customers that they may see the same twenty-five percent increase in songbirds at their feeders. Dr. E. Birde, Journal of Scientific Bird Feeding Which might be a cause for the increase in songbirds at the feeders?
the addition of dried apples and raisins to the formula
What does "Time (s)" represent in the graph?
the independent variable
Which of these time measurements is the smallest?
25,000 nanoseconds
How many milliseconds (ms) are there in 3.5 seconds (s)?
3,500 ms
Shawna is very knowledgeable about cars. She subscribes to several different automobile magazines, has interviewed people who work on cars for a living, and has researched many types of cars. She started a blog with the information she has gathered. On her blog, she offers opinions about which cars are the best value for the money and which are the most difficult to repair. Which best describes the reliability of her work?
It is unreliable because it offers opinions, not scientific facts.
Erwin Schrödinger developed the quantum model of the atom. What scientific knowledge was necessary for Schrödinger's work?
the discovery of the electron
Which source is the most reliable?
an article evaluated by other scientists
Which method is the typical first step when scientists communicate their scientific results?
submitting the results to a scientific journal for a peer review
A researcher wants to show the effects of slight changes in pH on the reproductive rates of fish in a lake. Why would a table be more suitable than a graph to show the data?
Tables better illustrate precise data points.
Cornell University recently conducted a study that estimated that honeybees pollinate more than $14 billion worth of crops, nuts, seeds, fruits, and vegetables each year. The study suggested that nearly seventy-five percent of all global crops that are grown for food, fiber, beverages, condiments, spices, and medicines are pollinated. Produced with the help of pollinators, agricultural products including legumes, vegetables, fruits, berries, nuts, herbs, spices, oils, seeds, grains, clover, and cotton make a significant contribution to the economy. As the human population increases, so does the demand for pollination; sadly, the honeybee population is decreasing. Within the past thirty years, parasites, predators, and disease have weakened both feral and managed populations of honeybees. In fact, around the globe, honeybees are being decimated by an epidemic known as colony collapse disorder (CCD). According to this article, who collected information to research the honeybees?
Cornell University
For centuries after Isaac Newton studied gravity, scientists accepted that gravity only exists between two objects that each have mass. However, new observations in the early twentieth century showed that even though light has no mass, it bends toward a planet as though it is forced by gravity. Albert Einstein used this observation, along with mathematical reasoning and many other observations, to redefine gravity and explain why both light and matter experience gravity's effects. Einstein's idea predicted many complex behaviors of nature that were later discovered, and because his idea consistently explains so many different observations it is now the basis for much of modern physics. Which best describes Einstein's new explanation of light and gravity?
Einstein created a new theory, because his explanation of the interaction between light and gravity provided unity amongst many facts.
Four students want to know the most accurate way to measure the speed of a wave. The method their professor uses has a percent error of 3.68%. Each student tests a different method and writes the result in the chart below. If the accepted value of a wave is 121 m/s, who has the most accurate method of measuring the speed of a wave?
Erin
During a conference presentation, a scientist described the materials that she used and how she performed her experiments. Which best explains why a scientist would share these details in a conference?
It informs the audience if the study included controlled tests.
When the first periodic table of the elements was published, the elements were arranged by atomic mass. Although several elements seemed out of order, later discoveries showed the order to be correct. Which event most likely helped the development of the periodic table?
New information changed the understanding of the atom's structure.
Which of these statements correctly compares probeware (such as an electronic temperature probe) to traditional analog tools (such as a liquid-based thermometer)?
Probeware is useful for obtaining many measurements in rapid succession.
The student performed an experiment to test his hypothesis about sunlight and plant height using two plants. He kept everything the same between two tomato plants except he exposed them to different amounts of sunlight. He also used a third plant as a control group, or a group in which no variables are manipulated to confirm the results. Roberto critiqued the work. Which problem did Roberto most likely identify?
The sample size is too small.
The electron cloud model is a modern theory about the structure of atoms that explains many of the atom's behaviors. According to the model, scientists imagine an atom to have a large nucleus of matter in the center surrounded by tiny particles called electrons. These electrons fly so fast and unpredictably around the nucleus that just one electron can appear to be a cloud. However, individual electrons are far too small for a human to see or touch. What is a limitation of the electron cloud model theory that a law about electrons would not have?
The theory provides an image that humans can visualize, but it does not fully represent how electrons exist.
Acupuncture is an alternative medicine that uses wire-thin needles inserted by a trained practitioner into specific points in the body. This ancient form of pain relief and stimulation is said to benefit patients by blocking channels which practitioners claim allow pain to travel within the body. This practice became more widely recognized and used after a New York Times reporter wrote in 1971 of a positive experience with it after surgery. Those who doubt the effectiveness of this treatment for pain attribute the pain relief to a placebo effect: if a patient believes something will reduce their pain, they will experience some relief. The National Institutes of Health says that acupuncture relieves pain and reduces nausea and vomiting, although it is unclear how it works. The few adverse effects reported are due to improperly sterilized needles or improper delivery, making this still a fairly low risk option. For anyone considering acupuncture, they should first research its effectiveness for their specific condition. Summary of statements published by the National Institutes of Health Which statement best explains the scientific claim about how acupuncture treatment reduces pain?
This ancient form of pain relief and stimulation is said to benefit patients by blocking channels which practitioners claim allow pain to travel within the body.
In 1917, after developing the concept of relativity, Einstein described how his findings supported the static universe idea, which was a widespread theory that stated that the size of the universe never changes. However, over the following decades, the theory of a static universe was disproved and replaced by the theory that the universe began with a "big bang" and has been expanding ever since. What most likely led to the change from the static universe theory to the expanding universe theory?
X new inquiries into the field of quantum physics, which is the study of the smallest possible objects
Henry plans to monitor the change in concentration of an acid during a chemical reaction. He wants to collect data every 0.1 seconds and then to graph his data and insert it into a text document. Which pair of tools would be best for Henry to use?
a computer and a concentration probe
In a recent survey of students who graduated from a large public high school, nine out of ten students reported that they passed biology with a grade of seventy-five percent or higher. What further data could be produced to be sure that this information is accurate?
a review of the students' school transcripts
Sian wants to measure the number of seconds that it takes for the contents of a beaker to change from clear to purple. Which of these tools should she use for this purpose?
a stopwatch
When can a theory be modified if a new type of technology allows for new observations that raise new questions?
after new hypotheses related to the theory are tested in experiments
In 1859, Charles Darwin published the first edition of On the Origin of Species, which explained his observations of various groups of animals that showed great similarities but minor differences. Darwin concluded that if a population of one species separates into two different populations that live in separate locations, then over the course of many generations the different populations can develop into different species. This idea predicted many future biological findings and became the basis of modern biology. Darwin's explanation for why different species exist is best described as a(n)
theory