A student sets up an experiment with two identical plastic tubes and a flat wooden board to verify the laws of reflection of sound. One tube directs the sound from a buzzer toward the board, and the second tube collects the reflected sound toward an observer. The axes of both tubes and the normal drawn at the point of incidence lie in the same horizontal plane.
(i) State the two laws of reflection of sound.
(ii) Draw a neat, labelled diagram of the experimental arrangement showing the incident ray, the reflected ray, the normal, the angle of incidence i, and the angle of reflection r.
(iii) The buzzer is replaced by another buzzer that produces a sound of twice the frequency. Keeping all geometrical arrangements unchanged, will the values of i and r change? Give a reason for your answer.