Concept
Sound moves through air because a vibrating source produces frequent variations in air
pressure. The frequency of the wave is the number of cycles of vibration per second.
At room temperature (20 degrees C), sound travels at 343 m/s.
Certain frequencies are naturally reinforced in hollow tubes.
When a tube is closed by a water boundary on one end, and open on the other end,
one quarter of a wavelength will resonate.
Materials
Tuning fork, rubber hammer, thermometer, large graduated cylinder, cold and hot water, meter stick, resonance tubes.
Procedure Part A
1. Fill the graduated cylinder with cold water.
2. Record the frequency of the tuning fork.
3. Place the resonance tube into the graduated cylinder.
4. Strike the tuning fork with the rubber hammer and hold above the top of the tube.
5. Adjust the height of the tube until the sound is loudest. Hold the tube still and measure and record the distance from the water to the top of the tube.
6. Hold a thermometer in the middle of the tube and record the air temperature.
Part B
1. Repeat the experiment with hot water in the graduated cylinder.
Analysis
1. Calculate the wavelength (?) of the sound waves for part A and B.
2. Calculate the speed of sound for part A and B.
3. Using the results from the experiment, does the speed of sound depend on air temperature? Explain why or why not.
