Which colour shows maximum deviation when passed through a prism ?

Options

A. Yellow
B. Red
C. Violet
D. Green

Explanation

To determine which color shows maximum deviation when passed through a prism, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Refraction**: When light passes through a prism, it bends due to refraction. The amount of bending depends on the wavelength of the light and the refractive index of the prism material.

2. **Angle of Deviation**: The angle of deviation (D) is defined as the angle between the incident ray and the refracted ray after passing through the prism. For small angles, the formula for the angle of deviation can be expressed as:
\[ D = (\mu - 1) \times A \]
where \( \mu \) is the refractive index of the prism for a specific color of light, and \( A \) is the angle of the prism.

3. **Refractive Index and Wavelength**: The refractive index (\( \mu \)) of a material varies with the wavelength of light. Generally, shorter wavelengths (like violet) have higher refractive indices, while longer wavelengths (like red) have lower refractive indices.

4. **Comparing Colors**: Among the visible spectrum, violet light has the shortest wavelength and therefore the highest refractive index. Conversely, red light has the longest wavelength and the lowest refractive index.

5. **Calculating Deviation**: Since the angle of deviation is directly proportional to the refractive index, we can conclude:
- For violet light: \( D \) is maximized because \( \mu \) is high.
- For red light: \( D \) is minimized because \( \mu \) is low.

6. **Conclusion**: Therefore, the color that shows maximum deviation when passed through a prism is **violet**.

### Final Answer:
The color that shows maximum deviation when passed through a prism is **violet**.

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