Posted by Sandhya on Sunday, November 9, 2008 at 5:29am.
1) Sound propagating through air at 30 degree Celsius passes through a vertical cold front into air that is 40 degree Celsius. If the sound has a frequency of 2400 Hz, by what percentage does its wavelength change in crossing the boundary?
(2) What is the intensity of a sound that has intensity level of (a) 50 dB or (b) 90 dB?

physics  drwls, Sunday, November 9, 2008 at 6:38am
(1) The sound speed increases in proportion to the square root of the absolute temperature change, sqrt (313/303) = 1.016. That is a 1.6% increase in sound speed and will result in a 1.6% increase in wavelength, since
wavelength = (sound speed)/(frequency)
2. Use the table at http://www.glenbrook.k12.il.us/GBSSCI/PHYS/CLASS/sound/u11l2b.html
to find your answer

physics  Sandhya, Monday, November 10, 2008 at 5:19am
Thanks for your easy solution for prob1
By the way is it not 1.016% ?
I solved prob 2 using the formula
Intensity level L = 10 log(I / I0) where I0 = 10^12 watt/sq.m
Answer This Question
Related Questions
 physics  A sound wave of frequency 1310 Hz., propagating through air at 0 ...
 PhysicsNeed Help fast!  Part 1 A 3m long pipe is in a room where the ...
 writting a program  Speed of Sound. Sound travels through air as a result of ...
 physics  A sound wave travels in air at a frequency of 500 Hz. If part of the ...
 physics!!!  A copper rod is given a sharp compressional blow at one end. The ...
 Physics  I know that sound has a lower pitch in colder air because the air is ...
 Physics waves check answer please  I would like to know if my answer is ...
 Physics waves check answer please  I would like to know if my answer is ...
 physics  a sound wave has frequency of 631 Hz in air and a wavelength of 0.54m...
 Physics  Sound  A sound wave travels in air at a frequency of 500 Hz. If part ...
More Related Questions