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Question
An object approaches a convergent lens from the left of the lens with a uniform speed 5 m/s and stops at the focus. The image ______.
Options
moves away from the lens with an uniform speed 5 m/s.
moves away from the lens with an uniform accleration.
moves away from the lens with a non-uniform acceleration.
moves towards the lens with a non-uniform acceleration.
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Solution
An object approaches a convergent lens from the left of the lens with a uniform speed 5 m/s and stops at the focus. The image moves away from the lens with a non-uniform acceleration.
Explanation:
In our problem the object approaches a convergent lens from the left of the lens with a uniform speed of 5 m/s, hence the image will move away from the lens with a non-uniform acceleration, the image moves slower in the beginning and faster later on will move from F to 2F and when the object moves from 2F to F, the image will move from 2F to infinity. At 2F, the speed of the object and image will be equal.
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