To investigate the relationship between the speed of sound in air through the pulse-echo experiment and the measured air temperature.
Hypothesis:
I believe the measured air temperature will affect the speed of sound because sound waves are longitudinal waves composed of the alternating compressions and rarefactions in air. If the air temperature is below 0°C, then the speed of sound would be lower than 331.6 m/s and if the air temperature is above 0°C, then the speed of sound would be higher than 331.6 m/s.
Materials:
Thermometer, closed cardboard tube, microphone, Data Studio software, metre stick, fingers
Procedure:
1. On the desktop, the Data Studio program was loaded and the materials were gathered.
2. Placed the microphone …show more content…
Clicked the start button on the Data Studio program as an individual snapped their fingers in between the microphone and the cardboard tube.
4. Approximately a second later, the program gathered the pulse-echo, the stop button was clicked to record the results and a screen shot was taken.
5. Steps 1 to 3 were repeated twice to complete a total of 3 trials.
Data and Observations:
Length of Cardboard tube: 1.25 m ± 0.2 m Measured Air Temperature: 23.0°C ± 0.5°C
Table 1: Start Time and Echo Time for Snap Sound Travelling in Closed Cardboard Tube
Data Analysis: T is the temperature measured in °C V is the speed of sound in air measured in m/s
V = 331.6 m/s + 0.606 T
V = 331.6 m/s + 0.606 (23.0°C)
V = 345.538
V = ~345.5 m/s
Therefore, the predicted speed of sound in air using the formula is about 345.5 …show more content…
Percentage difference = (|measurement1-measurement2| )/((measurement1+measurement2)/2)× 100% = (|353.8-345.5| )/((353.8+345.5)/2)× 100% = 8.3/((699.3)/2)× 100% = 8.3/349.65× 100% = 0.023738023 × 100% = 2.373802374% = ~2% Therefore, the percentage difference is approximately 2%.
Discussion:
The pulse-echo determination of the speed of sound, which is around 353.8 m/s, is reasonable to the speed of sound in air at 0°C, being 331.6 m/s, because the change of the air temperature in the room did affect the speed of sound. This investigation proves that as the room temperature increases, the sound wave is able to travel at a higher speed compared the room temperature being 0°C. Due to the molecules of air travelling at a faster speed in warm temperature, the vibrations of the sound waves are able to move more