Curriculum and Instruction

Activity Title: Pendulums

Essential Concepts & Skills:Iowa Core/Next Generation Science Standards, Grades 3-5.

Disciplinary Core Ideas:3-5-ETS1-3. Plan and carry out fair tests in which variables are controlled

and failure points are considered to identify aspects of a model or prototype that can be improved.

Science Practices: Planning and carrying out investigations Analyzing and interpreting data

21st Century Skills: Communicate and work productively with others Demonstrate productivity and accountability by producing quality work

What students will be doing: Students will be planning and carrying out fair tests using different variables to determine what makes a pendulum swing fast in 15 seconds. Students will be focusing on determining the independent, dependent variable, research questions, and conducting fair tests to make their claim.

Materials: Pencil Scissors String Washers Masking Tape Meter Stick Timers Student Thinking Log

Introducing the Activity: Introduce the activity by asking them What types of thing in our lives that

have a pendulum motion (back and forth motion)? Students may answer with swings, clocks, a ride at an amusement park, Newton’s Cradle, etc.

Those are all great examples! We’ve been discussing about controlling variables, constants, and conducting fair tests therefore today we’re going use that in an experiment about pendulums.

I would like for you to take a look at the first page of your thinking log. It asks you to give the definition of each word. I would like for you to write a complete sentence for each definition. Take some time now to write down the definitions. Use resources around you if needed.

Give students 5 to 7 minutes to write the definitions for each word. Once students have finished, bring the group together to discuss the criteria

for the pendulum activity as well as thinking log expectations. In your activity today, you are going to be determining what variable affects

the swing in your pendulum. One of the variables tested is displacement level. Does anyone know what it meant by displacement level? It is the point of where the pendulum is dropped. We will be measuring the displacement level by using a meter stick.

In order to test these variables, we need to determine what is a full swing. Ask students what they want as a full swing. Will it be a complete back and forth motion or from side to side? Once it has been decided, write in an area where it can be seen, such as the board, what is considered a full swing.

When we are testing the pendulums, the dependent variable needs to be measure. What are some ideas of how we can measure? Students will come up with some examples. Great examples, in this experiment we will be measuring using the timers. We are going to test the number of swings in 15 seconds.

Now that we have determined what a full swing is, what the displacement level means, and how we will measure the number of swings. I would like to discuss what needs to be done in your thinking log. For each experiment you will be asked to give a prediction. Write in a complete sentence what you think will happen. If in the end your prediction was wrong, DO NOT go back and change it. In your claim you will write you findings and it is ok that it is not the same as your prediction, in your groups I would like for you to set up your pendulum and test is out. Also, remember to write in complete sentences for every question or statement. In the data tables there are some blank spots, be sure to fill in everything. Remember your labels as well in your data tables.

Explain how to create the pendulums by wrapping string around the pencil and taping it with the masking tape. Then place the pencil on the edge of the table or desk and tape the pencil to the desk. The pendulum should not hit any chairs, tables or other obstacles. The pencil should not wobble either, if it does add more tape to secure the pencil from moving.

Give students time to create their pendulums and test them out. Walk around and help those who need it.

Once students have their pendulums, give them the go ahead to start on their experiment.

Teacher Notes: For center set up, have a tray for each group on the table. On the tray they

will find a timer, pencil, string, masking tape, meter stick and washers. The washers need to all be the same. Try to have more than 5 washers for each group so students can experiment with different weights for their pendulums.

When students are creating their pendulums, walk around and make sure that their strings are not hitting objects. If they are, they will have to restart the trial as it will affect the data. Also look for pencil that may be moving or wobbling around and add more tape to secure it.

Be looking out for students who are not writing complete sentences and remind them of the criteria.

Students should also be labeling in their data tables (cm, washers, in, etc.)

Pendulum Thinking LogGeneral Definitions: Write a general definition for each science term listed, so a person will know exactly how each was measured or what it means. Keep it generic - don’t mention pendulums for these first 7 terms!

Independent Variable: _______________________________________________ __________________________________________________________________

Dependent Variable: ________________________________________________ __________________________________________________________________ Constants: ________________________________________________________ __________________________________________________________________ Fair Test: __________________________________________________________ __________________________________________________________________ Research Question: __________________________________________________ __________________________________________________________________ Claim: ____________________________________________________________ __________________________________________________________________

Pendulum Experiment Details and Diagrams:Draw your pendulum experimental set-up and clearly label all of the parts. Also label how you will measure displacement.

How will you measure displacement in your pendulum experiment? ______________________________________________________________________________

How will the mass of the pendulum bob be measured in your experiment? _________________________________________________________________________

How will you count one pendulum swing in your experiment? ___________________________________________________________________________________

Pendulum Experiment #1: Displacement (Release Position)

What is the independent variable? _____________________________________

What is the dependent variable? ______________________________________

Research question (What we want to discover): What is the effect of ______________________ on the ___________________ in 15 seconds?

Prediction: (complete sentence) _________________________________________

_________________________________________________________________

Record the data for the constant variables in data table. Do the experiment then record the results in the data table.

Data Table 1: _____________________________________(Table title should list both independent and dependent variables.)

Number of Swings in 15 sec

Displacement Length of String

Mass Trial 1 Trial 2 Trial 3 Average

Write a claim (conclusion) about what you discovered in this experiment.

________________________________________________________________

________________________________________________________________

Pendulum Experiment #2: Mass

What is the independent variable? ______________________________________

What is the dependent variable? _______________________________________

Research question: __________________________________________________

__________________________________________________________________

Prediction: (complete sentence) __________________________________________

__________________________________________________________________

Correctly label all columns and rows in the data table and add a title.

Record the data for the constant variables in data table.Carry out the experiment then record the results in the data table.

Data Table 2: ____________________________________

Write a claim about what you discovered in this experiment. _______________

___________________________________________________________________

Pendulum Experiment #3: Length of String

What is the independent variable? ______________________________________

What is the dependent variable? _______________________________________

Research question: __________________________________________________

__________________________________________________________________

Prediction: (complete sentence) __________________________________________

__________________________________________________________________

Correctly label all columns and rows in the data table and add a title.

Record the data for the constant variables in data table.Carry out the experiment then record the results in the data table.

Data Table 3: ____________________________________

Write a claim about what you discovered in this experiment.________________

___________________________________________________________________

Write an overall claim about the variables that do and do not affect the rate of a pendulum’s swinging. ________________________________________________

___________________________________________________________________

Pendulum Thinking Log(Sample Answers)

General Definitions: Write a general definition for each science term listed, so a person will know exactly how each was measured or what it means. Keep it generic - don’t mention pendulums for these first 7 terms!

Independent Variable: An Independent variable is a variable that I change on purpose.

Dependent Variable: A dependent variable is a variable that is measured. Constants: A constant is what stays the same. Fair Test: A fair test is when the experimenter names the independent variable and dependent variable, all other variables remain constant, and data is recorded from at least 3 trials. Research Question: A research question is a yes or no question that names the independent and dependent variable.

Claim: A claim is drawing a conclusion by interpreting your data .

Pendulum Experiment Details and Diagrams:Draw your pendulum experimental set-up and clearly label all of the parts. Also label how you will measure displacement.

How will you measure displacement in your pendulum experiment? I will use a meter stick to measure the displacementHow will the mass of the pendulum bob be measured in your experiment? I will use washers to measure the mass.How will you count one pendulum swing in your experiment?

A full swing will be when the pendulum returns to the place where it was dropped will count as one swing.

Pendulum Experiment #1: Displacement (Release Position)

What is the independent variable? Displacement height

What is the dependent variable? Number of swings in 15 seconds

Research question (What we want to discover): What is the effect of displacement on the number of swings in 15 seconds?

Prediction: (complete sentence) The bigger the displacement, the more number of

swings the pendulum will have.

Record the data for the constant variables in data table. Do the experiment then record the results in the data table.

Data Table 1: Displacement vs Number of Swings in 15 Seconds(Table title should list both independent and dependent variables.)

Number of Swings in 15 sec

Displacement Length of String

Mass Trial 1 Trial 2 Trial 3 Average

20 cm 72.5 cm 2 washers 8 8 8 8

42 cm 72.5 cm 2 washers 8 8 8 8

78 cm 72.5 cm 2 washers 8 8 8 8

Write a claim (conclusion) about what you discovered in this experiment.

The average number of swings for each displacement level was the same,

therefore displacement level does not affect the number of swings.

Pendulum Experiment #2: Mass

What is the independent variable? The number of washers

What is the dependent variable? The number of swings in 15 seconds

Research question: What is the affect of the number of washers on the number

of swings in 15 seconds?

Prediction: (complete sentence) The more washers there are, the more number of swings the pendulum will have.

Correctly label all columns and rows in the data table and add a title.

Record the data for the constant variables in data table.Carry out the experiment then record the results in the data table.

Data Table 2: Number of Washers vs Number of Swings in 15 Seconds

Number Of Swings In 15 sec

Displacement Length of String Mass Trial 1 Trial 2 Trial 3 Average

42 cm 72.5cm 1 washer 8 8 8 8

42 cm 72.5 cm 3 washers 8 8 8 8

42 cm 72.5 cm 5 washers 8 8 8 8

Write a claim about what you discovered in this experiment.

The numbers of washers does not affect the number of swings.

Pendulum Experiment #3: Length of String

What is the independent variable? The length of string

What is the dependent variable? The number of swings in 15 seconds

Research question: What is the affect of the length of the string on the number of

swings?

Prediction: (complete sentence) The shorter the string, the more number of swings the pendulum will have.

Correctly label all columns and rows in the data table and add a title.

Record the data for the constant variables in data table.Carry out the experiment then record the results in the data table.

Data Table 3: Length of String vs Number of Swings in 15 Seconds

Number Of Swings In 15 sec

Displacement Length of String Mass Trial 1 Trial 2 Trial 3 Average

70 cm 59 cm 2 washers 9 9 9 9

70 cm 40 cm 2 washers 10 10 10 10

70 cm 24 cm 2 washers 13 13 13 13

Write a claim about what you discovered in this experiment.

The shorter the string, the greater number of swings in 15 seconds.

Write an overall claim about the variables that do and do not affect the rate of a

pendulum’s swinging.

The displacement level and number of washers do not affect the rate of the pendulums swinging but the length of string does.