# Homework Help: Establish formula f in terms of l, T and m

1. Jan 8, 2010

### area51

1. The problem statement, all variables and given/known dataQuestion: Assuming that the frequency of vibration f, of a wire/string depends on the length l, tension T and mass per unit length m, establish a formula for f in terms of l, T and m.,f, l, T and m

2. Relevant equationsDon"t know

3. The attempt at a solutionnot tried yet can any one help me in solving this. can anyone tell me how to solve it

2. Jan 8, 2010

### RoyalCat

At what level are you studying the subject?

There are two approaches possible here.

If you've only just started studying physics, then this is most likely a problem in dimensional analysis.

Assume that the frequency is a function of the mass per unit length, $$\mu$$, the total length of the wire, $$\ell$$ and the tension in the wire, $$T$$

$$f=\mu ^\alpha \cdot \ell ^ \beta \cdot T^ \gamma$$

Remember that the dimensions of the RHS must be exactly the same as those of the LHS.

I'll give you a lead, and say that the dimensions of frequency are: $$[f]=[T]^{-1}$$

If, however, you are studying this in a wave context, review your book and look at the section on waves in wires and look at the original question, since what you've posted can be interpreted as a multitude of things.