Calculating Wavelength in Water for Electromagnetic Radiation

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To calculate the wavelength of electromagnetic radiation in water, the formula used is wavelength(med) = wavelength(vac)/n, where n is the index of refraction for water, which is 1.33. Given a frequency of 5.00 x 10^14 Hz, the wavelength in a vacuum is calculated to be 600 nm. Dividing this by the index of refraction results in a wavelength of approximately 451 nm in water. The discussion emphasizes that the frequency remains constant while the wavelength decreases in a medium compared to a vacuum. This clarification helped resolve confusion regarding the calculations.
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Seriously, if I didn't need physics I probably wouldn't take it.I've don the work for this one problem, but then I'm not sure if it's the right formula for what I need. Here's what I have so far(the parts in bold are the work I've done)

10. An electromagnetic radiation has a frequency of 5.00 x 10^14Hz.
b) Calculate its wavelength in water.

Given: wavelength = 0.6 x 10^-6m or 600nm
n = 1.33 for water​
Required: wavelength(med)
Analysis: c=(f)(wavelength{vac}) and c=(n)(wavelength{med})

therefore wavelength(vac) = (n)(wavelength{med}) and​
wavelength(med) = wavelength(vac)/n​
Solution: wavelength(med) = (0.6 x 10^-6m)/1.33
= 4.51 x 10^-7 or 451 nm​
Now I get looking at this and I'm not sure if that's exactly how I go about doing this or if this is what I'm supposed to do for finding the index of refraction (which comes later) Please help, my brain is fried.
 
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You are correct. Remember, the wavelength of any frequency of light is always longest in a vacuum, shorter in a medium. Frequecy of the light stays constant.
 
Yay, thanks so much that was just driving me nuts
 
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