1. What is the Incident Angle?

The incident angle (i) is the angle between the incoming light ray and the normal (perpendicular line) to the surface at the point of incidence. It's a fundamental concept in optics that describes how light bends when passing between different media.

2. How Does the Calculator Work?

The calculator uses Snell's Law formula:

Where:

• \( i \) — Angle of incidence (degrees)
• \( n_1 \) — Refractive index of first medium
• \( n_2 \) — Refractive index of second medium
• \( r \) — Angle of refraction (degrees)

Explanation: The equation calculates how much light bends when passing from one medium to another with different refractive indices.

3. Importance of Incident Angle Calculation

Details: Calculating incident angles is crucial for designing lenses, optical fibers, and understanding phenomena like refraction, reflection, and total internal reflection.

4. Using the Calculator

Tips: Enter refractive indices (n₁ and n₂) as dimensionless numbers, and angle of refraction in degrees (0-90). All values must be positive.

5. Frequently Asked Questions (FAQ)

Q1: What is total internal reflection?
A: When light attempts to move from a medium with higher refractive index to lower but cannot refract, it completely reflects back. This occurs when the calculated sin(i) > 1.

Q2: What are typical refractive index values?
A: Air ≈1.0, Water ≈1.33, Glass ≈1.5, Diamond ≈2.4. The first medium must have lower or equal refractive index for valid results.

Q3: Why does light bend when changing media?
A: Light changes speed in different media, causing it to bend at the interface according to Snell's Law.

Q4: What's the critical angle?
A: The incident angle that produces a refraction angle of 90°. Calculated as arcsin(n₂/n₁) when n₁ > n₂.

Q5: Can this calculator handle complex refractive indices?
A: No, this calculator assumes real, positive refractive indices for transparent media.