# Transverse wave on a string

## Homework Statement

Two long strings P and Q ,each having linear mass density 1.2 x 10^-2
are stretched by a different tension 4.8 N and 7.5 N respectively and are kept parallel to each other with their left ends at x=0.Wave pulses are produced on the strings at t=0 on string P and at t=20ms at string Q.When and where will the pulses on Q overtake at on P.

## The Attempt at a Solution

Using the wave equation for the string ,I found the velocity at x=0 for P and Q to be 20m/s and 25m/s respectively.But I have one doubt about this question.Shouldn't speed of a wave in a string change with respective positions due to change in tension throughout the string......So does this not contradict the question

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Orodruin
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What change in tension?

palkia
Change in tension in a rope having masses incrases linearly throughout the rope

Orodruin
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You are thinking of a freely hanging rope. There is nothing in the problem formulation indicating that this is the case.

Also, you should always state units when giving values.

palkia
What is the difference between freely hanging rope and this case?

I will keep in mind to mention the units next time .

Orodruin
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A hanging rope has a gravitational force acting on it in its longitudinal direction. For force equilibrium, this means tension has to vary accordingly.

palkia
And what does this case look like...are we holding the rope?

Orodruin
Staff Emeritus