Question

Please do III.

Reflection and D 1L Transmission of multiple pulses o identical pulses are sent toward the boundary between the two springs illustrated below. For this part of the tutorial, ignore reflected pulses. n the two springs from section II, as Pulse 2 Pulse 1 Spring 1 Spring 2 A Boundary Suppose you measure the time interval ?, that begins when the leading edge of pulse 1 reaches point A and ends when the leading edge of pulse 2 reaches that same pont spring 1? Explain your reasoning. Predict whether this time interval would be different if you chose point A to lie in spring Would tis time interval be difet if you chosepoint A to lic atanother location along 2 rather than in spring 1. B. The following questions can be used to check your prediction above. 1. Consider the instant that the leading edge of pulse 1 reaches the boundary, as shown. Pulse 2 Pulse 1 Spring 1 Spring 2 Boundary Is the time that it will take for the leading edge of pulse 2 to travel from point B to the boundary greater than, less than, or equal to ?.? Explain your reasoning. On the diagram below, sketch a possible location of pulse 1 on spring 2 at the instant that the leading edge of pulse 2 reaches the boundary. Label the location of the leading edge of pulse l as point C 2. Pulse 2 Spring 1 Spring 2 Boundary Would the distance between the transmitted pulses be greater than, les r the distance between the incident pulses? Explain. or equal to is the time it took for pulse 1 to travel from the boundary to point C or equal to ?.? Explain your reasoning s your answer consistent with the prediction you made in part A2 you reconcile any differences? tion Group, Department of Physics

Answer 1

III.

A. time interval between the time when the leading edge of the pulse 1 reaches point A, and the leading edge of pulse 2 reaches on pint A depends only on the speed of the wave on the string

now, if the string is the same then the string speed of the wve will be the same

hence this time interval will be the same for any other point lying on string 1

if the point were to lie on string 2, then the time difference would be same

B. time taken for the point B to reach the edge of the boundary fromthe time the leading edge of pulse 1 reaches the boundary will be dt ( the same time interval as in the previous case)

C. in the given case string 2 is thicker than string 1

hence

followig is the expected shape of the string effected by wave 1

as we can see, the string 2 is thicker hence the speed of the wave 1 in string 2 is slower

hence distance between the transmitted pulse will be lesser than the distance between incident pulses as the speed of the wave in string 2 is slower

the time taken for the pulse to travel though will remain the same, as pulse 2 reached string 2 with a delay of the same time

hence, the prediciont from the first point is true