24P2Q03

3ai)

This is so that the sound waves emitted by X and Y are coherent.

3aii)

Connect a small microphone to a CRO.

Move the microphone along the straight line between X and Y and observe the amplitude of the sound wave on the CRO.

Use a ruler to measure the distance L between two consecutive maximum amplitude.

Wavelength is equal to 2L.$$

3bi)

$\displaystyle \begin{aligned}v&=f\lambda \\340&=f(0.40) \\f&=850\text{ Hz} \end{aligned}$

3bii)

xmPhysics