Question

A student is observing the diagram showing the path of a ray of light passing through a glass prism. He would find that for all angles of incidence the ray of light bends:​

Answer 1

A student is observing the diagram showing the path of a ray of light passing through a glass prism. He would find that for all angles of incidence the ray of light bends towards the base of the prism.

Reason:

• Let us assume that a ray of light is incident on the 1st surface of a glass prism. We know that refractive index of glass is greater than that of air.

• So, the light ray refracts and deviates towards the normal.

• Now , this light ray is incident on the 2nd surface off the glass prism. Now the ray is travelling from glass (denser) to air (rarer).

• So, the emergent ray deviates away from the normal.

• As a whole , it is observed that the net deviation of the light ray is towards the base of the prism.

• Refer to attached diagram.

• You can also see that in dispersion of white light , all the component colours are deviated towards the base of the prism.

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$\star$ Hope It Helps.

Answer 2

Answer:

towards the normal while entering the prism and away from the normal while emerging from the prism.

Explanation: