Why Is My Wavelength Calculation Incorrect?

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SUMMARY

The discussion centers on the calculation of wavelength (λ) from frequency (ω) for an electromagnetic wave in free space, specifically at a frequency of 7x1019 Hz. The correct relationship is established through the wave equation c = fλ, where c is the speed of light at 2.99792x108 m/s. The initial miscalculation arose from incorrectly using the angular frequency (ω) instead of the standard frequency (f). The correct wavelength calculation yields λ = c/f, which resolves the confusion between wavelength and wave number (k).

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What is the wavelength, k, corresponding to a frequency, w, of 7x10^19 Hz of electromagnetic wave in free space? The speed of light is 2.99792x10^8 m/s. Answer in units of m.
I set w/k=c
Plugging in (2*pi*7X10^19) for w, and 2.99792x10^8 for c, I got 1.467X10^12. The answer is wrong. Where did I go wrong?
 
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For one thing, the wave equation is [itex]c = f \lambda[/itex]. The frequency is in given in Hz; the wavelength (not wave number) has units of meters.

PS: Don't confuse wavelength with the wave number (k), which is generally defined as [itex]k = 2 \pi / \lambda[/itex]. If you want the wave number, then using [itex]k = \omega / c[/itex] will work.
 
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