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Question
What is a shadow? Give a reason for its formation.
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Solution
When light falls on an opaque object, light is obstructed and a dark patch on a screen kept behind is called a shadow. This is because light propagates in straight line. If the distance between the object and screen is less, the shadow will be (umbra) dark and smaller.
If the distance is increased shadow will be dim and larger.
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| O W S | A K E | O P A Q | U E O | B J E T | T S M |
| S H A D |
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