A ray of light falls normally on a rectangular glass slab.
Draw a ray diagram showing the path of the ray till it emerges out of the slab.

Explanation

To solve the problem of drawing a ray diagram for a ray of light falling normally on a rectangular glass slab, we will follow these steps:

### Step 1: Draw the rectangular glass slab
- Start by drawing a rectangle to represent the glass slab. Label the top side as the "Incident Surface" and the bottom side as the "Emergent Surface."

### Step 2: Draw the incident ray
- Since the ray of light falls normally on the slab, draw a straight vertical line (the incident ray) that meets the top side of the rectangle at a right angle (90 degrees). Label this line as "Incident Ray."

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