The wavelength of some red light is 700.5 nm. what is the frequency of this red light?

The frequency of the red light is 428 terahertz. To get the value of the red light's frequency, use the formula F = velocity/wavelength. The velocity of light is 3.00 x 10^8 m/s. For easier computation, convert 700.5 nanometers to meter. 1 nanometer is equal to 1 x 10^-9 meters. 700.5 nanometers is equal to 7.005 x 10^-7 meters. Divide the velocity 3.00 x 10^8m/s by wavelength 7.005 x 10^-7 meters. The result will be 4.28 x 10^14 Hertz or 428 terahertz.

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