A displacement–time graph for a point on a stretched wire shows that the point…

PHYSICS · Multi-part · A Level · Physics · Waves · Waves

Problem

A displacement–time graph for a point on a stretched wire shows that the point reaches successive positive maximum displacements at

t = 0.80\,\text{ms}

and again at

t = 3.20\,\text{ms}

. The greatest magnitude of the displacement on the graph is

4.5\,\text{mm}

. At the same time, a separate measurement shows that the distance between two consecutive crests on the wire is

0.75\,\text{m}

. Assume the motion is sinusoidal and that the wave propagates without loss. (a) Calculate the period

T

of the oscillation at the point on the wire. (b) Determine the frequency

f

of the wave. (c) Using the given wavelength, compute the speed

v

of the wave along the wire. (d) State the numerical value of the amplitude

A

and describe how it is identified on the displacement–time graph.