The critical angle for water is `48.2^@`. Find is refractive index.

Explanation

To find the refractive index of water using the critical angle, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Critical Angle**:
The critical angle (\( \theta_c \)) is the angle of incidence above which total internal reflection occurs when light travels from a denser medium to a less dense medium.

2. **Use the Formula for Refractive Index**:
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