---
title: Wave on Strings
topic: Waves
author: John Hopkinson
source: Physics_2019_122_Midterm_1_Q4
template_version: 1.4
attribution: standard
partialCredit: true
singleVariant: false
showCorrectAnswer: false
outcomes:
- 16.1.1.6
- 16.1.1.7
difficulty:
- undefined
randomization:
- undefined
taxonomy:
- undefined
span:
- undefined
length:
- undefined
tags:
- L.K
assets:
- reflectionstring.png
part1:
  type: number-input
  pl-customizations:
    rtol: 0.05
    weight: 1
    allow-blank: true
    label: $V_{\text{ratio}}= $
    suffix: null
part2:
  type: number-input
  pl-customizations:
    rtol: 0.05
    weight: 1
    allow-blank: true
    label: $t= $
    suffix: s
part3:
  type: number-input
  pl-customizations:
    rtol: 0.05
    weight: 1
    allow-blank: true
    label: $t= $
    suffix: s
part4:
  type: file-upload
  pl-customizations:
    file-names: file.png
myst:
  substitutions:
    params:
      vars:
        title: Wave on Strings
      t1: 4
      t2: 9
      v: 6
---
# {{ params.vars.title }}
<img src="reflectionstring.png" width=400 alt="snapshot graphs: (top) A wave pulse on a thin string approaches a short thick string followed by a thin string; (middle) at a later time the transmitted wave pulse into the thick string is shown; (bottom) at a still later time the reflected wave pulse in the middle of the thick string is shown;  the thin strings are left for you to draw on the middle and bottom graphs in (c).">

As shown in the figure above, a wave pulse travels from a light string to a heavy string. The thicker string has a linear mass density of {{ params.t1}} kgm while the thinner string has a linear mass density of {{ params.t2}} kgm.

## Part 1

Compare the speeds of the wave as it travels in the thick and thin strings. What is the ratio of the thin string velocity to the thicker string?

### Answer Section

Please enter in a numeric value.

## Part 2

The wave pulse travels at {{ params.v}} m/s within the thin string, where each vertical line represents {{ params.v}} m. The transmitted wave pulse first reaches the middle of the thick string as shown in the second diagram, and after reflecting off the end of the thick string returns to the middle of the thick string in the bottom diagram.

What is the time the second diagram occurs?

### Answer Section

Please enter in a numeric value.

## Part 3

Using the information from the previous question, what is the time the third diagram occurs?

### Answer Section

Please enter in a numeric value.

## Part 4

Draw and upload the shape of the thin strings (either flat or flat with a pulse of the same or opposite orientation and reduced amplitude) on either side of the thick string for the second two diagrams corresponding to the times that they occurred.

Your upload should be named 'file' and must be a png.

### Answer Section

File upload box will be shown here.

## Attribution

Problem is licensed under the [CC-BY-NC-SA 4.0 license](https://creativecommons.org/licenses/by-nc-sa/4.0/).<br> ![The Creative Commons 4.0 license requiring attribution-BY, non-commercial-NC, and share-alike-SA license.](https://raw.githubusercontent.com/firasm/bits/master/by-nc-sa.png)