(a(i))[1]
State the wave effect that enables the young teacher to hear the violin at the place where he is standing in Fig. 6.1.
(a(ii))[2]
Calculate the frequency of a sound wave with wavelength $0.75\,\text{m}$. The speed of sound in air is $340\,\text{m/s}$.
(a(iii))[2]
Explain why the young teacher hears the frequency calculated in (a)(ii) clearly, but a frequency of $3500\,\text{Hz}$ is much more difficult to hear.
(b)[3]
On Fig. 6.1: - draw a light ray from the violin to point X and then from point X to the teacher - draw and label the mirror - add an arrow to the ray to show how the teacher sees the student. Use a ruler and sharp pencil for this sketch.