What do you mean by pure spectrum ?

Explanation

### Step-by-Step Text Solution

1. **Definition of Spectrum**: A spectrum is a range of different colors produced when light is dispersed, typically through a prism. It represents the various wavelengths of light.

2. **Components of White Light**: White light is composed of multiple colors. When white light passes through a prism, it is separated into its constituent colors, which include violet, indigo, blue, green, yellow, orange, and red.

3. **Separation of Colors**: When light passes through a prism, it refracts and spreads out into these seven colors. This dispersion occurs because different wavelengths of light bend by different amounts when passing through the prism.

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