Two researchers, Elena and Farhan, are calibrating an acoustic rangefinder on a flat salt flat. They stand a distance of 240 m240\text{ m}240 m away from a sound generator that fires a blank cartridge while simultaneously flashing a bright LED. Each researcher starts their digital stopwatch when they see the LED flash, and stops it when they hear the bang.
Describe the nature of a sound wave and explain how it propagates through the air.
The researchers repeat this procedure five times and record their measurements in the table below:
| Researcher | Time readings (in s\text{s}s) |
|---|---|
| Elena | 0.69,0.72,0.71,0.68,0.700.69, 0.72, 0.71, 0.68, 0.700.69,0.72,0.71,0.68,0.70 |
| Farhan | 0.6,0.9,0.7,1.0,0.80.6, 0.9, 0.7, 1.0, 0.80.6,0.9,0.7,1.0,0.8 |
State the precision of Elena's stopwatch readings.
State the formula that relates speed, distance, and time.
Using the distance of 240 m240\text{ m}240 m, copy and complete the table below. Give all calculated values to an appropriate number of significant figures based on the precision of the raw data.
| Researcher | Mean (average) time (in s\text{s}s) | Speed of sound (in m/s\text{m/s}m/s) |
|---|---|---|
| Elena | ||
| Farhan |
The researchers find that the accepted value for the speed of sound in air at their current temperature is 341 m/s341\text{ m/s}341 m/s. They analyze their results:
Evaluate these conclusions, discussing the validity of their arguments concerning reaction time, precision, and accuracy.