# Resultant Frequency of two unlike soundwaves

1. Jan 30, 2012

### mckenna12

In a lab that my class was doing, we had to hit two tuning forks (of different frequencies) at the same time. One tuning fork had a frequency of 340 and the other had a frequency of 320Hz. I am aware that due to the Principle of Linear Superposition, when two sound waves are combined, the resultant is the sum of the disturbances from the individual waves.
My question is: what is the resultant frequency that is created? The amplitudes of the two waves are added together, but what about the two frequencies? Should it be around 330 Hz.... the average of 340 and 320Hz?

Thank you.
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

2. Jan 30, 2012

### Spinnor

You wrote,

"I am aware that due to the Principle of Linear Superposition, when two sound waves are combined, the resultant is the sum of the disturbances from the individual waves."

You need to first write down the functions that describe the two sources and then use the above.

See,

http://www.wolframalpha.com/input/?i=sin(320*2*pi*t)+++sin(340*2*pi*t)&cdf=1

You may need a plugin to view the above, its free and well worth the cost %^)

You may also want to find the trig identity for,

Sina + sinb

See "Sum-to-Product formulas" in,

http://www.sosmath.com/trig/Trig5/trig5/trig5.html