A student is using a wave flume to investigate the behaviour of water waves.
The student measures the time taken for 15 wavefronts to pass a reference marker on the wall of the flume. They repeat this measurement three times and calculate a mean. What is the advantage of repeating measurements and calculating a mean?
The student's three measurements for the time taken for 15 wavefronts to pass the reference marker are: 11.6 s,12.5 s,11.9 s11.6\text{ s}, \quad 12.5\text{ s}, \quad 11.9\text{ s}11.6 s,12.5 s,11.9 s Calculate the mean frequency of the wave. Give your final answer to 2 significant figures.
In a different part of the investigation, the student wants to determine the speed of the water waves. The student does not measure the wavelength of the waves. Explain how the student could determine the speed of the waves.