Science Assessment ~ Items ~ AP007007

A family is getting a pool in their backyard. They want to use the least amount of energy to keep the water in the pool warm. They can put the pool in the shade under some trees or in the open where sunlight will shine on it.

One family member thinks that they should put the pool in the sunlight. They think the sunlight will transfer energy to the pool so that they won’t need to use an electric heater to keep the pool warm. Another thinks it doesn't matter where the pool is placed because the sunlight does not transfer energy. They decide to do an experiment to see whether sunlight transfers energy to the pool.

Experimental Procedure

Step 1: Fill two cans with the same amount of water.

Step 2: Place one can in the backyard so sunlight shines on the can.

Step 3: Place the second can under an umbrella in the backyard so no sunlight can shine on it.

Step 4: Measure the temperature of the water in each can every hour using a thermometer.

1. Why will measuring the temperature of the water in the two cans help them figure out whether sunlight transfers energy?

2. If sunlight does transfer energy, what do you think would happen to the temperatures of the water in both cans during the experiment?

The family does the experiment twice. They measures the temperature of the water in each can every hour. The table below shows the data from their first experiment.

Experiment 1: Temperature Measurements

	Can with sunlight	Can without sunlight
Start	15 ^oC	15 ^oC
Time: 1 hour	16 ^oC	16 ^oC
Time: 2 hours	20 ^oC	16 ^oC

The second time they forget to make all the measurements. They measures the temperature of the water in the can in the sunlight after one hour and the temperature of the water in the can without sunlight after two hours. The table below shows the data from their second experiment.

Experiment 2: Temperature Measurements

	Can with sunlight	Can without sunlight
Start	15 ^oC	15 ^oC
Time: 1 hour	16 ^oC	No measurement taken
Time 2 hours	No measurement taken	16 ^oC

3. The family isn't sure whether the data from the second experiment is a fair comparison of the two cans. Explain why the second experiment is or is not a fair comparison.

4. Next, the family looks at the data from Experiment 1 to see if they can find patterns that would help them figure out whether sunlight transfers energy. What patterns do you notice in the temperature data from both cans of water in Experiment 1?

5. Now, think about the patterns you found in the data from Experiment 1 and what you know about energy. Do you think energy was transferred by sunlight to the water?

A. Yes, energy was transferred by sunlight to the water.

B. No, energy was not transferred by sunlight to the water.

6. Write an argument to support why you think energy was or was not transferred by sunlight to the water. Be sure your argument includes evidence from the family's experiment and uses what you know about energy.

Details
Performance
NGSS

Topic: 3D Energy Tasks
Scoring Rubric: Q1; Student either states or uses general science ideas

Changes in the temperature of an object are associated with energy being transferred to or from the object (i.e., if the can in the light increases in temperature, then the energy was trasnferred to the can, or if the water in the can gets warmer, you can assume the sun transferred energy to the water). [links changes in temperature and energy transfer]

Note: The student must use the word "energy" in their response and link it to a change in temperature (getting warmer is ok).; Q2; Student makes the correct prediction

The temperature of the water in the sunlight will increase AND the temperature of the water without sunlight will not increase or will increase less than the water in the sunlight.

Note: Student must reference both cans.

Note: It is acceptable to not specify which can is which. For example, "the temperature of one will increase and the temperature of the other will not."; Q3; Student uses the practice of planning and carrying out investigations

Fair tests require variables to be controlled (i.e. In order for the experiment to be a fair test, the temperature measurements of both cans must be made at the same time intervals. OR It's not a fair test because they are missing two data points.)

Note: Just stating "it's not a fair comparison" or "it's not a good test" is not acceptable.

Note: Discussing how the amount of energy transferred from the sun changes during the day is not acceptable.; Q4; Student identifies patterns

The can in the sunlight increased in temperature while the can in the shade remained the same.

OR

The can in the sunlight increased in temperature more than the can without sunlight.

Note: The student must indicate an increase in temperature not simply a change in temperature. They must also reference both cans.

Note: The student should indicate which can has which pattern. So "one is hotter than the other" is not acceptable. Citing the data is acceptable. For example, "One increased from 15 to 20 and the other only increased from 15 to 16."; Q5; Student selects answer choice A

A. Yes, energy was transferred by sunlight to the water.; Q6; 1. Student cites evidence to support their claim

The temperature of the water in the sunlight increased.

The temperature of the water without sunlight stayed the same [or increased a little].

2. Student either states or uses a general science idea

Changes in the temperature of an object indicate that energy was transferred to the water in the sunlight because it got hotter). [links increase in temperature and energy transfer]

3. Student uses reasoning to draw the correct conclusion from the experiment

The only difference between the cans was sunlight, so the difference in energy transfer must have been caused by the sunlight. [science idea-based reasoning]

OR

The can in the sunlight increased in temperature and the can in the shade didn't, therefore the sun must have transferred energy. [evidence-based reasoning]

Note: Students can only receive the reasoning point if they mention the temperature changes in both cans.

Percent of Points Earned

Chart showing distrubtion of responses for Item AP007007

Points Earned

	Avg. Earned	Possible	Percent
Q1	0.28	1	28%
Q2	0.43	1	43%
Q3	0.43	1	43%
Q4	0.37	1	37%
Q5	0.78	1	78%
Q6	1.01	3	34%

Overall Task Difficulty

	Total Points Earned	Total Points Possible	Total Percent
	3.31	8	41%

n = 237

Note: The total percent is a weighted average based on the total number of points earned divided by the total number of points possible.

Science and Engineering Practices: SEP3 Plan and conduct an investigation collaboratively to produce data to serve as the basis for evidence, using fair tests in which variables are controlled and the number of trials considered.
SEP3 Evaluate appropriate methods and/or tools for collecting data.
SEP3 Make predictions about what would happen if a variable changes.
SEP7 Construct and/or support an argument with evidence, data, and/or a model.
Crosscutting Concepts: CC1 Patterns in the natural and human designed world can be observed, used to describe phenomena, and used as evidence.
CC1 Patterns can be used as evidence to support an explanation.
Disciplinary Core Ideas: PS3.A Energy can be moved from place to place by moving objects or through sound, light, or electric currents.
PS3.B Energy is present whenever there are moving objects, sound, light, or heat. When objects collide, energy can be transferred from one object to another, thereby changing their motion. In such collisions, some energy is typically also transferred to the surrounding air; as a result, the air gets heated and sound is produced.
PS3.B Light also transfers energy from place to place.

Science Assessment

Item AP007007: Explain how the measurements made during an experiment involving sunlight address the experiment’s purpose. Evaluate the fairness of the experimental design. Identify patterns in temperature data and use the data to support an argument for the idea that sunlight transfers energy.