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krutre
09-04-2009, 05:39 PM
If the wavelength lambda in metres = 3 x 10e8 speed of light in metres divided by frequency in Hertz.
What would be the wavelength of red fight and the violet light in nano-metres?

JohnS
09-05-2009, 02:20 AM
If the wavelength lambda in metres = 3 x 10e8 speed of light in metres divided by frequency in Hertz.
What would be the wavelength of red fight and the violet light in nano-metres?

Minor correction the speed of light is measured in meters per second. Since the hertz is a reciprocal second, when the division is carried out, you will be left with meters.

This equation only helps you if you know the frequency of red and violet light. However, visible light is usually measured by wavelength. not frequency. Perception of red and violet persist over a range of wavelengths, but the extremes of visible light are usually taken as 400 nm and 700 nm (some use 750 nm). At 400 nm, the frequency is 750 THz, and at 750 nm, the frequency is 400 THz.

The very small wavelengths and high frequencies will give you some practice with prefixes.