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Question
An object is placed at a distance 20cm from a convex lens of focal length 10cm. Find the image distance and nature of the image.
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Solution
u = -20 cm
f = 10 cm
`1/"f"` = `1/"v"`- `1/"u"`
`1/"v"` = `1/"f"`+ `1/"u"`
`1/"v"`= `1/10`+`1/"(-120)"`
`1/"v"`=`1/10`- `1/20`
v = `1/20` ⇒ v = 20 cm
Nature of the image real enlarged and inverted image.
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