What is meant by dispersive power of a transparent material ?

Explanation

### Step-by-Step Solution:

1. **Understanding Dispersion**: Dispersion occurs when white light is separated into its constituent colors (spectrum) as it passes through a medium, such as a prism. This happens because different colors of light travel at different speeds in a medium.

2. **Thin Prism and Light**: When white light enters a thin prism, it bends or refracts at the surfaces of the prism. The amount of bending depends on the wavelength of the light.

3. **Angular Dispersion**: The angular dispersion is the angle between the emergent rays of the violet and red light. Violet light bends more than red light because it has a shorter wavelength.

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