Variables Assessment

Review

Swingers

• A pendulum is a mass hanging from a fixed point that is free to swing to and fro.

• A Cycle is any motion or activity that repeats itself.

• Variable is anything that you can change in an experiment that might affect the outcome.

• You need to control all of the variables, except for the one you are testing.

Question Answer Sheet

1. What is a variable?

2. What is a pendulum?

3. What variables might affect the number of cycles the pendulum makes in 15 seconds?

1. Anything that can change in an experiment that might affect the outcome.

2. A mass hanging from a fixed point that is free to swing to and fro.

3. Mass, length and starting position.

What Scientist Do

• What are the steps involved in scientific Inquiry?

• Make Observations• Ask questions based on observations• State a hypothesis• Test the hypothesis (Experiment)• Observe the results and draw conclusions• Communicate the results

Question/Answer Sheet

4. What are the steps involve in scientific inquiry?

5. What is a controlled experiment?

6. Can scientist learn about the world without doing a controlled experiment?

4. Observation, ask question, hypothesis, experiment, observe results and draw conclusions and communicate.

5. When you control all the variables in an experiment except the one being tested.

6. Yes, scientist learn from observation of the natural world.

Swingers

• Standard is the basic procedure used in a controlled experiment, before changing any of the variables

• An Experiment is an investigation designed to find out how variables affect outcomes

• Controlled Experiment is an experiment which one variable is changed and the out come is compared to the standard.

Question/Answer Sheet7. Which variables made

no difference in the number of swings?

8. Which variable did make a difference in the number of swings?

9. What is the relationship between the length of a pendulum and the number of swings it makes in a unit of time?

7. Mass and release position

8. Length

9. As the length of the pendulum increases, the number of swings decreases.

Swingers

• A prediction is an estimate based on information or experience.

Graphs

• Concrete Graph – Example: Swingers hanging from the number line

• Pictorial Graph– Example: Drawing of the swingers on the number line

• Two-Coordinate Graph– Example: Dots to symbolize the real objects– Definition: Shows the outcome of a series of

experiments when a variable is changed by steps.

Question/Answer Sheet

10.How can you predict how many swings an 80cm pendulum will make in 15 seconds?

10.If one variable is known, a two coordinate graph can be used to predict the value of its corresponding variable.

Lifeboats

• Capacity is the greatest amount of fluid a container can hold.

Question/Answer Sheet

1. What variables might affect the number of passengers a paper-cup boat can hold.

1. Where the pennies are placed in the cup, water movement, and the size of the cup.

Controlled Experiment

• All the variables are controlled, or kept constant, except one, so that the experimenter can observe the effect of that one variable on the outcome of the experiment

Independent/Dependent Variables

• If you wanted to make a graph of the results of your lifeboat experiment, what are the two variables you would graph?

• Which variable did you know before the experiment started?(Independent Variable)

• What is the dependent variable?

Question/Answer Sheet

2. Is there a relationship between the capacity of lifeboats and the number of passengers they hold?

2. The greater the capacity, the more passengers a boat can hold.

Question/Answer Sheet

• How can you predict the number of passengers a new boat will hold?

• You can predict using a two coordinate graph.

Independent Variable (Unit)

Dep

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(Uni

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0 1 2 3 4 5 6 7 8 9 10

0

1 2

3

4

5

6

7

8

9

10

Title

•Be Neat

•Use a pencil

•Use a ruler

Flippers Question/Answer Sheet

1. Describe the flipper system. Why is it called a system?

1. The flipper system is a flipper base, flipper stick, cork, and push stick all working together.

Question/Answer Sheet

2. What variables might affect the distance a ball will fly?

3. What is the relationship between the mass of a foil ball and the distance it flies?

2. Distance of the flip can be affected by mass of the ball, size of the ball, angle of launch, length of the flip stick, how far you press down the flip stick and the position of the ball.

3. The lighter the ball the farther it will fly.

Question/Answer Sheet

4. Why do scientists conduct multiple trials of the same variable?

4. Multiple trials improve the accuracy of experimental results.