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Required practical - measuring waves in a solid

Measure the frequency, wavelength and speed of waves in a solid

There are many different ways that the speed of waves in a solid can be measured. This is one of the methods.

Aim of the experiment

To measure the frequency, wavelength and speed of waves in a metal rod.

Method

  1. Using the first finger and thumb on one hand, hold a metal rod at its middle point.
  2. Hit one end of the rod with a hammer.
  3. Hold a smartphone with an app which measures frequency near the end of the rod.
  4. Record the peak frequency from the phone app.
  5. Measure the length of the metal rod and record the length.
  6. Calculate the speed of the sound waves in the rod using the frequency and wavelength recorded.

Results

Here is an example of how the results table could look:

Frequency (Hz) Length of rod (m)Wavelength (m)Wavespeed (m/s)
............
Frequency (Hz)...
Length of rod (m)...
Wavelength (m)...
Wavespeed (m/s)...

Analysis

State the frequency, wavelength and speed of waves measured in the solid.

Hazards and control measures

HazardConsequenceControl measures
Dropping rod or hammerInjury from falling objectsTake care to hold equipment carefully
HazardDropping rod or hammer
ConsequenceInjury from falling objects
Control measuresTake care to hold equipment carefully