The wavelength of violet light is 4.0 x 10−7 m. the wavelength of red light is 6.5 x 10−7 m. how much longer is the wavelength of red than violet?

2.5 x 10^-7 m

Explanation:

We can substract the wavength of the violet light to the wavelength of the red light:

(6.5 x 10^-7 m) - (4.0 x 10^-7 m) = 2.5 x 10^-7 m

This is the difference between this two values of wavelength.

So the wavelength of red light is 2.5 x 10^-7 m longer than violet light.

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