An arrangement for generating stationary waves in air inside a tube that is closed at one end is shown in Fig. 6.1. A loudspeaker produces sound waves of wavelength $0.680\,\text{m}$ in the tube. For certain values of the tube length $L$, stationary waves are produced.
(a)[2]
Explain how stationary waves are produced in the tube.
(b(i))[2]
The length $L$ is varied from $0.200\,\text{m}$ to $1.00\,\text{m}$. Calculate two values of $L$ for which stationary waves are produced.
(b(ii))[1]
On Fig. 6.2, mark the positions of the antinodes with an A and the nodes with an N for the smallest value of $L$ for which a stationary wave is produced.
Worked solution & mark scheme
This 5-mark question has a full step-by-step worked solution and mark scheme. One marking point: “sound waves from loudspeaker move down tube and are reflected at the closed end; two waves travelling in opposite directions with the same frequency/wavelength superpose” …