Physics 1
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Practice Problems: Evidence-Based Scientific Argumentation
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1.(easy) A question is raised in a science class about why there are seasons for much of the Earth. Identify the claim, evidence and justification in the poorly made argument shown below that was created to answer the question. Critique the argument using the concepts discussed in the presentation.
"Everyone understands the concept that the closer you are to a source of heat, the warmer it is. Seasons occur because the Sun is closest to the Earth during the summertime in North America. We know this because the average temperature in Pittsburgh is the highest in June, July, and August."

2. (moderate) Read through the following information about a hypothetical experiment and respond to the prompt that follows: Two groups of high school science students gathered data from an experiment that could be characterized by several different variables. Among these variables are the number of ticks and tocks. The students could control the number of ticks associated with the system and then measure the number of tocks that the system presented. Data from five trials for each of the groups is shown here:

Choose one claim from the following list:

  • The results from both groups are in agreement.
  • The results from the two groups don’t agree.
  • It’s unclear as to whether the results agree or disagree.

In a pargraph-length response, support your choice as fully as you can.

3. (moderate) The following scenarios were found in a research study titled Using a Pseudoscience Activity to Teach Critical Thinking (Adam and Manson, 2014 - see citation below). For each scenario, identify any claim, evidence, or justification (rationale) statements. Then state why each is flawed.

Scenario 1: Bill’s mom told him that taking vitamin C will cure a cold. The very next time Bill caught a cold he drank three glasses of orange juice every day for 5 days. Orange juice contains vitamin C. At the end of the fifth day, Bill’s cold was gone. Bill concluded that vitamin C cures colds.

Scenario 2: A famous Nobel Prize–winning scientist announces that magnets can relieve back pain when rubbed on a person’s back. He found 10 people with back pain and gave each of them magnet therapy. After the therapy, most of the people told him that their back pain was reduced. He concluded that magnets relieve back pain.

Scenario 3: You see a new ad for a pill that enhances the body’s natural ability to concentrate while driving. The ad features a famous race car driver who races a track he has never raced on both before and after taking the pill. He does much better the second time after taking the pill. The ad concludes that taking this pill will enhance your driving abilities.

Scenario 4: A teacher feels better when wearing bright colors. She hypothesizes that wearing brightly colored clothing can also improve the mood of people around her. She tests this using her students. She wears dull clothing to her morning class of 45 students and brightly colored clothing to her afternoon class of 45 students. She reports that her afternoon class seemed more alert and smiled more. She concludes that wearing bright colors improves other peoples’ moods.

4. (moderate) All scientific arguments are not equal. Some are better than others. Since arguments are composed of three distinct components, it's often helpful to analyze the strength of each component in an argument. The following information helps one to determine the strength of the various components:

Claims: Strong claims answer the question being asked. Strong claims indicate cause and effect, often using the word "because" and are written in complete sentences.

Evidence: Evidence is strong when it is based on a pattern in the data. Strong evidence is reliable in that it comes from multiple trials or observations. Strong evidence doesn't violate known physical laws. An evidence statement is strengthened when it is combined with other evidence that also supports the claim.
Justification: Strong justification uses science terms appropriately and uses accepted scientific concepts to explain the connection between the claim and the evidence. 
Imagine that you were tasked with answering the following question:

"When a woman is on a moving walkway (the kind you see at airports) and tosses a ball vertically into the air, why doesn't the ball land behind her?"

a. Rank the following claims from weakest to strongest:
Claim #1: The ball will not land behind her because it was already moving forward (relative to the ground, not the moving sidewalk) prior to the vertical toss.
Claim #2: The ball will not land behind her because I've never seen that happen.
Claim #3: The ball will not land behind her because gravity pulls it downward.

b. Rank the following evidence statements from weakest to strongest:
Evidence Statement #1: I observed this phenomenon many times at the airport. The ball never lands behind the person tossing it.
Evidence Statement #2: When an object is dropped from an airplane, it doesn't fall straight downward. Instead it continues moving forward while it falls.
Evidence Statement #3: I watched the woman conduct the experiment.

c. Rank the following justifications from weakest to strongest:
Justification #1: The conservation of energy is a bedrock scientific principle. If the ball landed behind the woman, this principle would be violated.
Justification #2: Gravitational force is described by a physical law which states that all masses attract all other masses. The ball must fall down toward the Earth.
Justification #3: The physical concept of inertia is a well established scientific fact. It states that an object continues in its state of motion unless acted on by a net external force. Although the gravitational force acted vertically, no significant force acted horizontally. (We are assuming negligible air resistance.)

5. (moderate) Examine the image of Angel's Landing in Utah's Zion National Park. Note how there are trees and other vegetation at one level (above the base) on the mountain. Choose one claim below that explains why there are trees at that level and not others. You must include evidence and reasoning in your answer.
Claim 1: Erosion does not occur at that level.
Claim 2: Erosion from the upper layers form top soil at that level.
Claim 3: More water drains to that level than other levels.
Angels Landing Zion

6. (moderate) There is an active organization (The Flat Earth Society) whose members claim to believe that the Earth is flat. They believe this for many reasons, primarily that their personal perceptions (sense data) support the concept of a flat Earth. One famous flat Earther, basketball star Shaquille O'Neal actually stated that he believes the Earth is flat because it appears flat to him when he drives from Florida to California. Members of this society also support their claim with theoretical concepts. For example, they believe that circumnavigation is possible because the North Pole is at the center of the Earth and that Antarctica is a massive ice-wall that surrounds the flat Earth. So, one can follow any circular path around the North Pole and end up where they started.

Flat Earth map

Flat Earth theorists explain day and night cycles by the movement of the Sun around the North Pole. The Sun is like a flashlight, illuminating only part of the earth at one time.

Day/night cycle on a Flat Earth

The seasons are explained in flat Earth theory by claiming that the Sun varies its distance from the Earth throughout the year. Gravity is explained by claiming that the earth is always accelerating upward (like the initial movement of an elevator), creating the perception of weight. And by the way, any photos taken from space are manipulated to make the the Earth appear round (a conspiracy led by NASA).

a. Create a pseudo-scientific argument using this information, then identify why the argument is invalid.
b. Create a scientific argument in support of the Earth being round.

Adam, A., & Manson, T. M. (2014). Using a pseudoscience activity to teach critical thinking.Teaching of Psychology, 41(2), 130-134. doi:10.1177/0098628314530343

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