Sunil is a student of class VIII in a public school in Delhi. During summer vacation, his parents planned a visit to Haridwar by their car. During the journey from Delhi to Haridwar, Sunil sat on the front seat and his father was driving the car. Sunil observed that the road ahead on the highway appears to be wet but when the car reached the spot, road is found to be dry. He was perplexed by this observation. He asked his father. His father advised Sunil not to disturb him during driving and said that he will discuss the problem on reaching Haridwar. In the evening, when they were settled in a hotel at Haridwar, Sunil’s father told him that the illusion observed by Sunil was on account of atmospheric refraction. Now, Sunil was happy as he knew the real explanation of his observation.

(i) What is atmospheric refraction?


(ii) Name any two phenomena based on atmospheric refraction


(iii)What characteristic was shown by Sunil during his journey?


(iv) What advice was given by Sunil’s father to him and why?

(i) In the atmosphere we have air layers having different optical densities. When the light rays pass through the atmosphere then refraction of light takes place. The refraction of light caused by the earth’s atmosphere (having varying optical densities) is called atmospheric refraction.


(ii) Two phenomenon based on atmospheric refraction are


Twinkling of stars at night


Advanced sunrise and delayed sunset.


(iii) Curiosity and an urge to learn are shown by Sunil during his journey.


(iv) His father advised Sunil not to disturb him during driving because it may lead to distraction. One should drive very carefully and should not be distracted for a safe journey.


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