CPO Science Integrated Physics & Chemistry Chapter 11.1

Harmonic Motion

Developing A Model

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What does harmonic motion mean?

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What are some examples of harmonic motion?

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What is the difference between linear motion and harmonic motion?

Key Questions

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What is harmonic motion?

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How do we describe the back and forth motion of a pendulum?

Developing An Experiment

 What variables effect the pendulums period?

— Mass, amplitude, and length — How can we change the variables?

 What material will we need?

 What data needs to be collected?

— Period, How can we calculate period?

 2 times the timer — Length, mass, and amplitude

Run The Experiment

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Set up the Pendulum

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Tips:

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How many variables can you test at a time?

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If you think one variable may effect the period, test it first to the extreme.

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Work as a group to help keep variables constant.

What did you learn?

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What did you discover about the three variables?

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Why didn’t mass and amplitude affect the period?

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Mass gravity is constant

—

Amplitude conservation of energy



Graph the data that you have

What did you learn?

Developing An Experiment

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Why does the amplitude change during the experiment?

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Friction



Where does the friction come from?

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We call the friction in harmonic motion damping

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Have you ever experienced damping?

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How long does damping take in the pendulum?

What Did You Learn?

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What did you discover about the two variables?

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What would you want to have in order to reduce the effect of damping?

—

Large mass & long length

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Graph the data that you have

Summary

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What is harmonic motion?

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Is a pendulum harmonic motion?

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How do we describe the motion of the pendulum?

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What affect does damping have on the pendulum

?