Science Worksheet: Identifying Variables | PDF - Free Printable

Problem: Identifying Variables in Scientific Experiments

The task is to identify the dependent variable, independent variable, and control variable (if applicable) for each scenario described in the worksheet. Below is a detailed explanation and solution for each question.

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1. Two groups of sixth graders were tested to compare their speed in solving long division problems. One group had calculators, the other didn't.

- Dependent Variable: The speed in solving long division problems is the outcome being measured. It depends on whether or not the students used calculators.

- Independent Variable: The use of calculators is the factor being manipulated. One group has calculators, and the other does not.

- Control Variable: The grade level (sixth grade) and the type of problem (long division) are control variables because they remain constant across both groups.

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2. Students of different grades were given the same jigsaw puzzle to assemble. The time they took to assemble it was measured.

- Dependent Variable: The time taken to assemble the jigsaw puzzle is the outcome being measured. It depends on the grade level of the students.

- Independent Variable: The grade level of the students is the factor being manipulated. Different grades are compared.

- Control Variable: The jigsaw puzzle itself is a control variable because it is the same for all students.

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3. Sasha wanted to figure out what type of liquid worked best for growing beans. She watered one with coca-cola, one with lemonade, and one with just water. After one week, she measured how high they had grown.

- Dependent Variable: The height of the beans after one week is the outcome being measured. It depends on the type of liquid used.

- Independent Variable: The type of liquid used to water the beans (coca-cola, lemonade, or water) is the factor being manipulated.

- Control Variable: The type of bean plant, the amount of sunlight, the soil quality, and the watering frequency are control variables because they remain constant across all groups.

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4. Miss Kobayashi wanted to find out what fertilizer works best in growing Marigolds. She put Miracle Grow on the first pot of Marigold, then Scotts Fertilizer on the second pot of Marigold, and no fertilizer on the third pot.

- Dependent Variable: The growth of the Marigolds (e.g., height, number of flowers, overall health) is the outcome being measured. It depends on the type of fertilizer used.

- Independent Variable: The type of fertilizer applied (Miracle Grow, Scotts Fertilizer, or no fertilizer) is the factor being manipulated.

- Control Variable: The type of Marigold plant, the amount of sunlight, the soil quality, and the watering frequency are control variables because they remain constant across all pots.

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5. Luffy wanted to see if eating apples would help him do better on his classwork. The first day, he didn’t eat any apples. On the 2nd day, he ate one apple; on the 3rd day, he ate 2 apples; and on the 4th day, he ate 3 apples. Each day, he recorded the grades he got on his science work.

- Dependent Variable: The grades he got on his science work are the outcome being measured. They depend on the number of apples eaten.

- Independent Variable: The number of apples eaten per day (0, 1, 2, or 3) is the factor being manipulated.

- Control Variable: The science work itself, the difficulty of the assignments, and Luffy's general study habits are control variables because they remain constant across the days.

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Final Answers:

1.
- Dependent Variable: Speed in solving long division problems
- Independent Variable: Use of calculators
- Control Variable: Grade level (sixth grade), type of problem

2.
- Dependent Variable: Time taken to assemble the jigsaw puzzle
- Independent Variable: Grade level of students
- Control Variable: Jigsaw puzzle

3.
- Dependent Variable: Height of beans after one week
- Independent Variable: Type of liquid used to water the beans
- Control Variable: Type of bean plant, sunlight, soil quality, watering frequency

4.
- Dependent Variable: Growth of Marigolds
- Independent Variable: Type of fertilizer applied
- Control Variable: Type of Marigold plant, sunlight, soil quality, watering frequency

5.
- Dependent Variable: Grades on science work
- Independent Variable: Number of apples eaten per day

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Final Boxed Answers:

1.
- Dependent Variable: Speed in solving long division problems
- Independent Variable: Use of calculators
- Control Variable: Grade level (sixth grade), type of problem

2.
- Dependent Variable: Time taken to assemble the jigsaw puzzle
- Independent Variable: Grade level of students
- Control Variable: Jigsaw puzzle

3.
- Dependent Variable: Height of beans after one week
- Independent Variable: Type of liquid used to water the beans
- Control Variable: Type of bean plant, sunlight, soil quality, watering frequency

4.
- Dependent Variable: Growth of Marigolds
- Independent Variable: Type of fertilizer applied
- Control Variable: Type of Marigold plant, sunlight, soil quality, watering frequency

5.
- Dependent Variable: Grades on science work
- Independent Variable: Number of apples eaten per day

\boxed{See above for detailed answers.}