Calculate Wavelength Without Frequency

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Homework Statement

A ray of light from the sun strikes the windshield of a car at an angle of incidence of 36.0° and refracts at an angle of 24.0°. If the initial light had a wavelength of 630 nm, determine the wavelength of the light after it has refracted.

Relevant Equations

n1sintheta1=n2sintheta2

n1sintheta1=n2sintheta2
1*sin36=n2sin24
n2=sin36/sin24
n2= 1.45
to calculate wavelength is lambda=c/f
My question is that that how do I find the wavelength without given the frequency.

 

[Drakkith]

My question is that that how do I find the wavelength without given the frequency.

You already have the frequency. It's the same frequency both before and after the light enters n2.

 

[bbbbb]

so i will do f=c/wavelength
Then to find lamda2= c/f.
So I am not using the angles given.