Which of the following shows the bending of light from denser (D) medium into a rarer (R) medium?

Options

A.
B.
C.
D.

Answer

To determine which diagram shows the bending of light from a denser medium to a rarer medium, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Concept of Refraction**:
- Refraction occurs when light passes from one medium to another and changes speed, causing it to change direction. When light travels from a denser medium (higher refractive index) to a rarer medium (lower refractive index), it bends away from the normal.

2. **Identify the Denser and Rarer Mediums**:
- Let’s denote the denser medium as (D) and the rarer medium as (R). The refractive index of the denser medium (μD) is greater than that of the rarer medium (μR).

3. **Applying Snell's Law**:
- Snell's Law states:
\[ μD \cdot \sin(I) = μR \cdot \sin(R) \]
- Here, I is the angle of incidence and R is the angle of refraction.

4. **Analyzing the Relationship Between Angles**:
- Since μD > μR, we can rearrange Snell's Law to find the relationship between the angles:
\[ \frac{μD}{μR} = \frac{\sin(R)}{\sin(I)} \]
- This implies that:
\[ \sin(R) > \sin(I) \]
- Therefore, angle R (angle of refraction) must be greater than angle I (angle of incidence).

5. **Identifying the Correct Diagram**:
- We need to find the diagram where the angle of refraction (R) is greater than the angle of incidence (I).
- In the options given:
- If a diagram shows \( R > I \), it is the correct representation of light bending from a denser medium to a rarer medium.

6. **Evaluating the Options**:
- **Option 1**: Angle of incidence equals angle of refraction (I = R) – Incorrect.
- **Option 2**: Angle of incidence less than angle of refraction (I < R) – Correct.
- **Option 3**: Angle of incidence greater than angle of refraction (I > R) – Incorrect.
- **Option 4**: Angle of incidence less than angle of refraction but showing total internal reflection – Incorrect.

7. **Conclusion**:
- The correct option that shows the bending of light from a denser medium to a rarer medium is **Option 2**, where the angle of incidence is less than the angle of refraction.