Q16 of 48 Page 1

An object of height 6 cm is placed perpendicular to the principal axis of a concave lens of focal length 5 cm. Use lens formula to determine the position, size and nature of the image if the distance of the object from the lens is 10 cm.

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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