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Questions
An object is placed at a distance of 10 cm from a convex lens of focal length 12 cm, find out at what distance image will be formed from the lens and what is the nature of image.
An object is placed at a distance of 10 c.m a convex lens of focal length 12 c.m found at what distance the object placed from the lens. position and nature of image.
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Solution
Given:
Focal length (f) = 12 cm,
Object distance (u) = −10 cm
To find: i. Image distance (v)
ii. Nature of image
Formula: `1/"f" = 1/"v" - 1/"u"`
Calculation: From the formula,
`1/12 = 1/"v" - 1/(- 10)`
∴ `1/"v" = 1/12 - 1/10`
`= (10 - 12)/120`
`= (- 2)/120`
`= - 1/60`
∴ v = -60 cm
A negative sign indicates an image is formed on the same side as that of the object.
The image is erect, virtual and magnified.
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