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Question
A lens forms the image of an object placed at a distance 15 cm from it, at a distance 60 cm in front of it. Find the magnification.
Solution
Object distance, u = -15 cm
Image distance, v = -60 cm
For a lens, magnification is
`"m" = "v"/"u"`
`therefore "m" = (-60)/-15`
∴ m = + 4
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