Estimating organ pipe frequency from a photograph

[physicsdawg]

Question about sound frequency of an organ...?

Homework Statement

Based on this picture from the Jehmlich organ manufacturer in Dresden, Germany, estimate the frequency of sound produced by the organ pipe held by the man. Assume that the pipe is a tube open at both ends.
http://cache.daylife.com/imageserve/01iq4P0e330tQ/610x.jpg

Homework Equations

The Attempt at a Solution

I feel like the formula to be used is Fn=n(V/4L)...I am not sure how to estimate length (maybe 1.5 m based on the size of the person?) And ahve no idea what n would be, or if I am evenusing the right formula...any experts...?

 

[alphysicist]

Hi physicsdawg,

Homework Statement

Based on this picture from the Jehmlich organ manufacturer in Dresden, Germany, estimate the frequency of sound produced by the organ pipe held by the man. Assume that the pipe is a tube open at both ends.
http://cache.daylife.com/imageserve/01iq4P0e330tQ/610x.jpg

Homework Equations

The Attempt at a Solution

I feel like the formula to be used is Fn=n(V/4L)...I am not sure how to estimate length (maybe 1.5 m based on the size of the person?) And ahve no idea what n would be, or if I am evenusing the right formula...any experts...?

No, I don't believe your equation is correct. That equation applies to the case of a tube with only one end open. Since the problem says assume that both ends are open, what formula do you get?

 

[physicsdawg]

your right, it should be a 2L...from the picture I determine the length to be 1.5...what do you think of this estimation?

and how do I figure out what N equals??Thanx

 

[alphysicist]

your right, it should be a 2L...from the picture I determine the length to be 1.5...what do you think of this estimation?

and how do I figure out what N equals??Thanx

I believe your length estimate is okay; it seems to me like they just want you to find a rough estimate.

About N, I would think that they want you to find the fundamental frequency.

 

[physicsdawg]

so just assume n=1? Then I get the final answer to be square root (344/3) = 114.6 m/s

does this look right??>

 

[alphysicist]

so just assume n=1? Then I get the final answer to be square root (344/3) = 114.6 m/s

does this look right??>

The answer looks okay to me (are significant figures important?), but why did you say square root?