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प्रश्न
Using mirror formula, explain why does a convex mirror always produce a virtual image.
उत्तर
For a convex mirror,
Focal length, f > 0
Position of object, u < 0
From mirror formula, we have
`1/f=1/v+1/u=>1/v=1/f-1/u`
`=>1/v>0`
∴v>0
This means that the image formed by a convex lens is always behind the mirror and hence, virtual.
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