# Tuning fork frequency help

1. Sep 24, 2008

### Shackleford

6. A tuning fork is heard to resonate over a resonance tube when the
air column is 48.5 cm long and again when it is 68.7 cm long. What is
the frequency of the tuning fork if the temperature is 26˚C?

I couldn't figure out how to work this. I thought it mattered if it were in a closed or open pipe, which is not mentioned.

v = 346.6 m/s

2. Sep 24, 2008

### Foxhound101

Re: Frequency

I had a problem that was similar to this...if I recall correctly, lambda was .5(D2-D1). So lambda is half the distance between resonances.

>_> However, I am not an expert and could very easily be wrong.

3. Sep 27, 2008

### Shackleford

Re: Frequency

Don't I have to know if it's open or closed?

4. Oct 1, 2008

### Shackleford

Re: Frequency

lambda = 2 (l2 - l2) - .404 m

v = 346.4 ms^-1

f = 857.4 Hz

5. Oct 1, 2008

### abelanger

Re: Frequency

First you ll need to get the v-air which is given by: v = (332.5)(squareroot(T/273))
where T is the temperature in Kelvin. After that you know that v = f x lambda, and now i think: Ln+1 - Ln = 1/2 lambda.