In an experiment to trace the path of a ray of light through a triangular glass prism, a student would observe that the emergent ray

Options

A. is parallel to the incident ray.
B. is along the same direction of incident ray.
C. gets deviated and bends towards the thinner part of the prism.
D. gets deviated and bends towards the thicker part (base) of the prism.

Explanation

To solve the question regarding the path of a ray of light through a triangular glass prism, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Prism**: A triangular glass prism has three faces, and when light passes through it, it undergoes refraction. The prism is denser than air, which affects the direction of the light ray.

2. **Incident Ray**: When a ray of light enters the prism from air, it first hits the surface of the prism. At this point, we need to consider the normal (an imaginary line perpendicular to the surface at the point of incidence).

3. **Refraction at the First Surface**: As the ray enters the prism, it slows down due to the higher refractive index of glass compared to air. According to Snell's law, the ray bends towards the normal.

4. **Path Inside the Prism**: Inside the prism, the light travels in a straight line until it reaches the second surface of the prism.

5. **Refraction at the Second Surface**: When the ray reaches the second surface (the exit point), it is moving from a denser medium (glass) to a rarer medium (air). At this point, the ray will bend away from the normal.

6. **Emergent Ray Direction**: The emergent ray will exit the prism at an angle that is determined by the geometry of the prism and the laws of refraction. In this case, the emergent ray will be deviated and will bend towards the base of the prism.

7. **Conclusion**: Therefore, the correct observation is that the emergent ray gets deviated and bent toward the thicker part of the prism (the base).

### Final Answer:
The emergent ray gets deviated and bent toward the thicker part of the prism.

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