Question
How does a concave lens act as a ‘diverging lens’?
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Answer
In a concave lens, the upper half of the lens has the bases of the prisms upwards and the lower half of the lens has the bases of the prisms downwards. Therefore in this lens, the rays of light suffer divergence in the upwards direction, and in the lower half, the rays diverge in the downward direction. On being produced backward by dotted lines, these rays appear to diverge from a point F.
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