In a demonstration, a teacher uses a loud ticking clock, two hollow tubes A and B, a barrier and a smooth surface. The clock is used as a source of sound. Fig. 4.1 shows tube A and the clock, both fixed in position on the left of the barrier. [Figure 4.1] Sound from the ticking clock passes along tube A and is incident on the smooth surface. A student listens to the sound passing along tube B, which is on the right of the barrier.

1. (a)(i)On Fig. 4.1, draw tube B in the position where the sound heard by the student is loudest.[1]
2. (a)(ii)Explain your answer to (i).[2]
3. (b)The speed of sound in air is 330 m/s. State a typical value for the speed of sound in a solid.[1]

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