What is the beat frequency of two strings with different tensions?

AI Thread Summary
The discussion centers on calculating the beat frequency of two strings with different tensions, specifically with a tension difference of 0.25 N. The relationship between frequency and tension is highlighted, with attempts to derive the beat frequency using the equation f1/f2 proportional to the square root of tension. A simplification approach is suggested, indicating that the small tension difference allows for an approximation that leads to a formula for the beat frequency. The conclusion emphasizes that the resulting frequency depends on the tension and properties of the strings, and there is a suggestion to clarify the question with the professor.
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Homework Statement



Two strings with otherwise identical properties differ in tension by 0.25 N. If both strings are struck at the same time, what is the resulting beat frequency?

Homework Equations



frequency is proportional to the root of tension?

The Attempt at a Solution



I tried setting T2 = T1 - 0.25 N and substituting this into an equation with f1/f2 proportional to sqrt{T1/T2}.

But I can't seem to figure anything out from this.

Please help! Going a bit crazy.
 
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I can't make anything of it either.

If I put f_1 = k \sqrt {T} and

f_2 = k \sqrt {T + 0.25}

I get

f_2 - f_1 = k \sqrt {T+0.25} - k \sqrt {T}

wich I can't simplify further.

0.25 N is probably quite small compared to the tension in the string, so we can apply

\sqrt {T+0.25} \approx \sqrt {T} + 0.25 \frac {1} {2 \sqrt {T}}

this results in

f_2 - f_1 \approx \frac {0.125 k} {\sqrt{T}}

so the answer does depend on the tension, and the other properties of the string as well.
 
willem2 said:
I can't make anything of it either.

If I put f_1 = k \sqrt {T} and

f_2 = k \sqrt {T + 0.25}

I get

f_2 - f_1 = k \sqrt {T+0.25} - k \sqrt {T}

wich I can't simplify further.

0.25 N is probably quite small compared to the tension in the string, so we can apply

\sqrt {T+0.25} \approx \sqrt {T} + 0.25 \frac {1} {2 \sqrt {T}}

this results in

f_2 - f_1 \approx \frac {0.125 k} {\sqrt{T}}

so the answer does depend on the tension, and the other properties of the string as well.

thank you so much willem. i don't think my prof worded the question properly, so I'm going to ask him tomorrow. thanks again!
 
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