Changing pitch in frequency ratio?

[Mickey Tee]

Homework Statement

Homework Equations

v=fΛ

v=√(T/μ)

The Attempt at a Solution

I know I'm supposed to make an attempt, but I can make heads nor tails of this. Are they changed in a constant ratioo? Does the tension come into play?

The answer given is 0.16m

 

[berkeman]

Homework Statement

View attachment 771

What's weird too is that they are saying the frequency goes down, but decreasing string length should make the frequency go up...

 

[haruspex]

What's weird too is that they are saying the frequency goes down, but decreasing string length should make the frequency go up...

Well, it says the ratio 4/5, which maybe should be read 4:5. It doesn't say "to 4/5".
Mickey, tension doesn't come into it because the tension isn't changing. You quote two equations, one of which is relevant, and gives the right answer.

 

[Mickey Tee]

Ohh, the only way I was picturing it was the strings being slackened or maybe a reversal of elastic elongation. :P Too much thought into a simple question.

 

[haruspex]

Ohh, the only way I was picturing it was the strings being slackened or maybe a reversal of elastic elongation. :P Too much thought into a simple question.

Okay! Yes, it's annoying when you get locked into a misreading like that.

 

[Mickey Tee]

Thanks!

And by the way, a very happy new year to you haru! :D
May it bring you many new experiences.

 

[onkar0027]

For strings the frequency is given by
f=1/2L sqroot(t/m)

Now f is inversely proportional to length of string

Use this relation to find the answer