Question

how you can Say that light have seven colour

Answer 1

Hi
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Light is made up of wavelengths of light, and each wavelength is a particular colour. The colour we see is a result of which wavelengths are reflected back to our eyes.

Light is made up of wavelengths of light, and each wavelength is a particular colour. The colour we see is a result of which wavelengths are reflected back to our eyes.

The visible spectrum

The visible spectrum showing the wavelengths of each of the component colours. The spectrum ranges from dark red at 700 nm to violet at 400 nm.

Visible light

Visible light is the small part within the electromagnetic spectrum that human eyes are sensitive to and can detect.

Visible light waves consist of different wavelengths. The colour of visible light depends on its wavelength. These wavelengths range from 700 nm at the red end of the spectrum to 400 nm at the violet end.

White light is actually made of all of the colours of the rainbow because it contains all wavelengths, and it is described as polychromatic light. Light from a torch or the Sun is a good example of this.

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Hope it helps

Answer 2

Light is a combination of 7 colours as when we passes light through a prism different lights depending on their wave length gets refracted and clear boundaries of 7 different colour light s can be seen.
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