(a)[1]
The balloon and the two microphones lie along one straight line. The student bursts the balloon with a pin, producing a loud sound. The sound is picked up first by the microphone at A and then by the microphone at B. The oscilloscope traces for this are shown in Fig. 2.2. The oscilloscope timebase is set to $0.50\,\text{ms division}^{-1}$. Use Fig. 2.2 to calculate the time taken for the sound to move from A to B.
(b)[1]
Suggest one reason why the student did not position microphone A at the $0.0\,\text{cm}$ mark on this metre rule.
(c)[1]
Use the equation $v = \frac{\text{distance travelled}}{\text{time taken}}$ to find the speed $v$ of sound.
(d)[1]
Suggest one method the student can use with the same apparatus to get a more accurate value for $v$.