Q14 of 25 Page 10

A 6 cm tall object is placed perpendicular to the principal axis of a convex lens of focal length 15 cm. The distance of the object from the lens is 10 cm. Find the position, size and nature of the image formed, using the lens formula. ( CBSE 2013, 2012)

Given: Height of the object, h1 = 6 cm

Focal length of the concave mirror, f = -5 cm


Object distance, u = -10 cm


Applying the lens formula:






v= -3.3 cm


Now, as we know magnification is given by:



Equating both we get





h2=+2 cm


The image will be virtual, erect and diminished in size.

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