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Question
What is the position of image when an object is placed at a distance of 10 cm from a convex lens of focal length 10 cm?
Solution
Given:
Object distance, u = -10 cm
(Since object is always placed on the left side of lens)
Focal length, f = +10 cm
According to lens formula:
`1/v-1/u=1/f`
`1/v=1/f+1/u`
`1/v=1/10=(-1/10)=0`
`v=1/0= oo`
Therefore, the position of image will be at infinity.
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