~christina~

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**[SOLVED] simple standing wave question- not exactly sure why I can't get answer?!**

**1. Homework Statement**

A particle fingering flute sounds note with frequency of 880Hz at 20 deg celcius(343m/s => sound wave speed) The flute is open at both ends.

a) find the air column length

b) find the frequency the flute produces at begining of football game when ambient temp is -50.0C and muscician has not had time to warm up flute.

answers supposed to be=> a) 0.195m and b) 841m

**2. Homework Equations**

[tex]f= n\frac{v} {2L} [/tex]

[tex]v= f*\lambda [/tex]

**3. The Attempt at a Solution**

**a) find the air column length**

I really did try to do this and what I did was I got

v= 343m/s

f= 800Hz

[tex]342.91m/s= 800Hz \lambda[/tex]

[tex]\lambda= 2L [/tex]

**L= 0.206875m**=> not the answer in the book?!

**b) find the frequency the flute produces at begining of football game when ambient temp is -50.0C and muscician has not had time to warm up flute.**

[tex]v= 331 \sqrt(1 + 20^oC/273^oC)= 299.1567m/s [/tex]

based on L before:

L= 0.206875m

[tex]f= v\lambda= 288.15e69/0.41375= 723.0378[/tex]

**=> why isnt' this matching the book answer??**

Please help...

it's really a simple problem I think.

**THANK YOU**

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