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Sunrays pass through a pinhole in the ro...

Sunrays pass through a pinhole in the roof of a hut and produce an elliptical spot on the floor. The minor and major axes of the spot are 6 cm and 12 cm respectively. The angle subtended by the diameter of the sun at our eye is `0.5°`. Calculate the height of the roof.

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The correct Answer is:
`3.44 cm`
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Knowledge Check

  • Two rings are suspended from the points A and B on the ceiling of a room with the help of strings of length 1.2 m each as shown. The points A and B are separated from each other by a distance AB = 1.2 m. A boy standing on the floor throws a small ball so that it passes through the two rings whose diameter is slightly greater than the ball. At the moment when the boy throws the ball, his hand is at a height of 1.0 m above the floor. A stop watch which is switched on at the moment of throwing the ball reads 0.2 s when the ball passes through the first ring and 0.6 s when it passes through the second ring. The angle of projection of the ball is:

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