Tuning Forks & Sound

    Sound is created by vibrating matter.  Different rates of vibration (frequency) create sounds of different pitch.  Tuning forks have a rate of vibration or frequency stamped on them.  The frequency is measured in vibrations per second or hertz.

Purpose:  The purpose of this lab is to compare tuning forks and investigate sound.

                    Materials
            Tuning fork        Rubber mallet
            beaker & water    paper



Procedure:   NOTE!! Always strike a tuning fork with a mallet , never strike a tuning fork on a hard surface.

1. Hold a tuning fork and tap it with a rubber mallet.  Can you hear the sound?  Can you see the fork vibrating?
2. Tap a second fork.
3. Compare and contrast the pitch and  frequencies of the forks.  What is the relationship between frequency and the pitch of the sound the fork produces.
4. Tap each fork again. Hold a piece of paper in the air and touch the tuning fork to it. Record your observations.
5. Tap each fork again.  Lower the prongs into a glass of water.  Record your observations.
6. Tap a fork again.  Wave it nearer and farther from your ear. Describe what happens to the pitch.  

Conclusions:
    Are you convinced that the sound of forks is the result of vibrating matter? Explain.


    Describe the relationship between frequency and the pitch of the sound.

    

    Explain how  pitch is our perception of the frequency of  sound.