Springs and Swings:Hands-on Discovery

Welcome!

Who is CPO Science?

• Developer and publisher of inquiry-based science curriculum and hands-on materials• How many have heard of CPO Science?• Sample materials at your table – PLEASE LEAVE FOR OTHER WORKSHOPS – WE CAN MAIL SAMPLES – Thanks very much!

How is CPO Science Different?• We design and manufacture high quality

science equipment and INCLUDE IT with purchase of textbook sets

• We support guided inquiry through extensive teacher support material and reader-friendly texts

• We offer strong science content that is a blend of conceptual and quantitative approaches.

What Subject Areas?• High School: Physical Science, Earth/Space

Science, Physics First, CP Physics• Middle School: Earth, Life, Physical• Visit the booth• Request samples with raffle forms at end of

workshop

Now for the fun!

What is a “spring constant” a measure of?

• Force per unit of extension or compression

Which extension spring has a larger spring constant?

• You have a white-tabbed and a blue-tabbed extension spring

Use the data table to guide you as you collect data for each spring

Extension (cm)

Forc

e (N

)

GRAPH DATA FOR BOTH

SPRINGS!

What are the spring constants?

Hooke’s Law (springs)

• Use your graph or the equation to predict how much the blue-tabbed spring would extend with 15 washers, then test your prediction

Hmm…

• Why do you get an extension prediction that is higher than the experimental result if you use the Hooke’s Law equation?

Collect data to graph and find the spring constant for the compression spring

Compression (cm)

Forc

e (N

)Create a graph!

Let’s go from springs to SWINGS!

• Set up a pendulum

Press and hold GO button to turn on the DataCollector

Plug the photogate into Photogate A port

Choose CPO Timer Mode

Choose the period function in Timer Mode.

• Period is the time for one complete cycle. Since the pendulum breaks the beam once as it swings through a complete cycle, the DataCollector’s readout equals the time it takes the pendulum to complete one full cycle.

Which has the biggest effect on the period: length, mass, or amplitude?

• Design an experiment to find out. Change each variable 3 times so you can create 3 graphs of 3 data points each. Take careful data, because you will compete against other groups in the accurate clock contest!

Clock Challenge!

• Using your data, design and construct a pendulum that you can use to accurately measure a 30-second time interval. When it’s your group’s turn, you will demonstrate the accuracy of your clock by telling us when to stop a running stopwatch (that you cannot see!)

Build an Oscillator!

• Use blue-tabbed spring• 7 washers• DataCollector:– CPO Timer Mode– Period function

Natural Frequency

• Find the natural period • Calculate the natural

frequency

Design another oscillator

• Build an oscillator that has a HIGHER natural frequency

• Build an oscillator that has a LOWER natural frequency