Variables Module

Investigation #1

Date Activity Page #

8-14-07 Pendulums/Swingers 4

How many cycles will a 38 cm pendulum complete in

15 seconds with

the mass of one penny?

My 38 cm pendulum will swing ______ times in 15 seconds with the mass of

one penny.

1. pendulum/swinger2. timer

1. Construct a 38 cm pendulum.

2. Swing the pendulum and record how many cycles it completes in 15 second

3. Complete #2 three times and average your results.

Test ## of

completed cycles

12

3

Average

If a penny is placed at the end of a 38 cm pendulum made out of string and a

paper clip, then it will complete ______cycles in

15 seconds.

1. Pendulum – a mass hanging from a fixed point that is free to swing back and forth

2. Cycle – any motion or activity that repeats itself

3. Variable – anything that you can change in an experiment that might affect the outcome

What variables affect the number of cycles your

pendulum will complete in 15 seconds?

1. What would happen if you changed the release position of the pendulum?

2. What would happen if you changed the mass of the pendulum?

3. What would happen if you changed the length of the pendulum?

SwingersInvestigation 1

Part 2

1. How will the release of position of the pendulum affect the number of cycles a pendulum will complete in 15 seconds?

2. How will changing the mass of the pendulum affect the number of cycles a pendulum will complete in 15 seconds?

1. If I change the release of position, then the number of cycles will_________ because _________.

2. If I change the mass of the pendulum, then the number of cycles will _____________ because _______________.

1. pendulum/swinger2. timer3. pennies

1. Swing the pendulum at the determined position of release and record how many cycles it completes in 15 second.

2. Complete #2 three times and average your results.

3. Swing the pendulum with the new mass and record how many cycles it completes in 15 second.

4. Complete #2 three times and average your results.

Release of Position

Test #Angle of Release Number of Cycles

And Average

1 45 degrees ___, ___, ___ =

2 90 degrees

3 180 degrees

Change of Mass

Test # MassNumber of Cycles

and Average

1 2 pennies ___, ___, ___ =

2 small washer

3 large washer

List the variables that were used and what you determined from the

results.

Investigation 1 Part 3

How will the length of the pendulum affect the number

of cycles a pendulum will complete in 15 seconds?

I predict that the number of cycles completed in 15

seconds will _________ as the pendulum length increases, and it will __________as the pendulum length decreases

because _________________.

Length of the Pendulum

# of cycles completed in 15 seconds

10 cm

17 cm

22 cm

30 cm

45 cm

55 cm

70 cm

90 cm

120 cm

170 cm

The number of cycles completed in 15 seconds ________ as the

pendulum length increases,

and it __________ as the pendulum length decreases.

1. Name three things that you have learned while doing this

investigation.2. Name two things that surprised

you during this investigation.3. Name one question that you have

now that you have completed this investigation.

1. What is a variable?2. What is a pendulum and where

have you seen one?3. What variables might affect the

number of cycles the pendulum makes in 15 seconds?