The refractive indicates of flint glass for red and violent colours are `1.644 "and" 1.664`. Calculate its dispersive power.

Explanation

To calculate the dispersive power of flint glass given the refractive indices for red and violet colors, we can follow these steps:

### Step 1: Identify the refractive indices
We are given:
- Refractive index for red color, \( \mu_r = 1.644 \)
- Refractive index for violet color, \( \mu_v = 1.664 \)

### Step 2: Calculate the mean refractive index
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