# Help with Transverse Wave Equation

1. Dec 14, 2010

### vividcolours

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

Two vibrating sources emit waves in the same elastic medium. The first source has a frequency of 25 Hz, while the 2nd source's frequency is 75 Hz. Waves from the first source have a wavelength of 6.0 m. They reflect from a barrier back into the original medium, with an angle of reflection of 25 degrees. Waves from the second source refract into a different medium with an angle of incidence of 35 degrees. The speed of the refracted wave is observed to be 96 m/s.

I need to find the speed of waves from the second source in the originial medium and if the angle of refraction of the waves from the second source are greater, less or equal to 35 degrees as they enter the different medium.

2. Relevant equations
The universal wave equation is V = (f)(L)
V = speed
f = frequency
L = wavelength

also f = 1/T
T = period (time) f anf t are reciprocals of each other

3. The attempt at a solution

Given: f = 75Hz
refracted v = 96m/s
angle of incidence = 35 degrees

Required: speed (v)
wavelength (L)

Analysis: V = (f)(L)
= (75)(?)

I just don't know how to find either the v or the L as this is the only formula I've been given and I can't use it with two variables. I tried making a graph with the angles but didn't have enough information. I don't know if I can somehow use the angles to calculate the refracted wave's original speed or if there's a way to use the refracted wave's speed to calculate the original speed. This is a grade eleven physics problem and I am so frustrated with this and can't see a way to solve it. If someone could even just help me find the wavelength of the second source that would help a lot.

2. Dec 15, 2010

### vividcolours

Can anybody help with this?