Who discovered by his experiments with glass prisms that white light consists of seven colours?

Options

A. Newton
B. Faraday
C. Maxwell
D. Young

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the scientist who discovered that white light is made up of seven colors through experiments with glass prisms.

2. **Identifying the Scientist**: The scientist known for this discovery is Sir Isaac Newton. He conducted experiments with glass prisms in the late 17th century.

3. **Newton's Experiment**: Newton used a glass prism to refract white light, which resulted in the separation of light into its constituent colors. He observed that when white light passes through a prism, it splits into a spectrum of colors.

4. **The Seven Colors**: The seven colors that Newton identified in the spectrum are Red, Orange, Yellow, Green, Blue, Indigo, and Violet. This is often remembered by the acronym ROYGBIV.

5. **Understanding Refraction**: The phenomenon of light bending when it passes from one medium to another (like air to glass) is called refraction. Different colors of light have different wavelengths, which causes them to refract at different angles.

6. **Conclusion**: Therefore, Sir Isaac Newton is credited with the discovery that white light consists of seven colors through his experiments with glass prisms.

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