Physics Lab Speed of Sound in Air

Physics Waves Lab SL

Introduction:

This lab will investigate the properties of mechanical waves such as a longitudinal wave, focusing on the question: Does a change in the frequency of a wave result in a significant and convincing change in the speed of the wave?

Hypothesis: Changing the frequency of the wave will not result in a change in speed because the wavelength will change proportionally as in theory.

Student Designed Investigation

Procedure/ Planning

Procedure:

1. Three students would get into a group.

2. A Slinky would be spread along a table or along the floor and set up as it shows on the diagram above for about 4 meters.

1. For proper data, the length of the floor was measured and marked with a tape.

2. A student would make small waves, while another would time it with a stopwatch until it reaches the other side. This step would be repeated, however the wave would be bigger or smaller, in order to find out if changing the frequency, the speed would change.

3. With the data recoded for many different waves, the velocity would be compared for all of them.

Materials:

1. Slinky

2. Role-up meter stick

3. Stopwatch

4. Tape

5. Pen/Pencil

6. Three Lab partners

Proposal (diagram) of each Trial:

Trial 1: Trial 2: Trial 3:

Trial 4: Trial 5:

Planning:

According to theory, as frequency changes, the wavelength will change proportionally; therefore, speed will remain the same. By following the procedure that our student design recommends, it will successfully control the variables that should not be changed, such as the slinky, its stretch distance, and the temperature, in order to prove the theory above. The independent variable would be the frequency of the wave, which would change in every trial, while the dependent would be time, which would later be used to find the speed of the traveling wave. In order to collect data, two students would hold the slinky while on would