Question 1
Paper 2Medium9 marksTwo transverse pulses travel in opposite directions along the same string. At one instant, they overlap. The individual displacements of the pulses at three positions on the string are shown below. Displacements are measured from the equilibrium position; upward displacements are positive.
| Position, x / cm | Pulse A displacement / cm | Pulse B displacement / cm |
|---|---|---|
| 1.0 | +2.0 | +1.0 |
| 2.0 | +4.0 | −4.0 |
| 3.0 | +2.0 | −1.0 |
(a)[1]
State the displacement of pulse A at x = 2.0 cm.
(b)[3]
Determine the displacement of the string at each of the three positions.
(c)[2]
Identify whether the interference at x = 3.0 cm is constructive or destructive. Explain your answer using the data.
(d)[3]
At x = 2.0 cm, the resultant displacement is zero. Explain why this does not mean that the pulses have been destroyed, and describe their motion and shape once they have passed through one another completely.