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A convex lens makes a real image 4 cm lo...

A convex lens makes a real image 4 cm long on a screen. When the lens is shifted to a new position without disturbing the object, we again get a real image on the screen which is 16 cm tall. The length of the object must be

A

`1//4` cm

B

8 cm

C

12 cm

D

20 cm

Text Solution

Verified by Experts

The correct Answer is:
B
Object height
`h_(0) = sqrt(h_(l_(1)) h_(l_(2)) ) = sqrt(4 xx 16) = 8 `cm.
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