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How do I find the color of the threshold wavelength if the metal has a threshold wavelength of $\mathrm{6.5\times 10^{-7}m}$? I know that converts down to $\mathrm{650\ nm}$, but can I still use the visible color spectrum's wavelengths to find the color or is it different for metal?

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Hi Mia. If you're interested in finding colors, then there are many online calculators like this one ;-) – Waffle's Crazy Peanut Apr 28 '13 at 2:30
Thank you so much!!! – Mia Garbaccio Apr 28 '13 at 5:44
up vote 1 down vote accepted

The metal's threshold wavelength is a wavelength of light. So yes, you would use a chart converting wavelengths of light to the color to identify it. For some metals, the threshold wavelength is not visible light; it might be ultraviolet. But whatever chart you're using would identify the wavelength you have as either ultraviolet or visible, and which color it is.

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