Q5 of 50 Page 43

An object is placed perpendicular to the principle axis of concave lens of focal length 30cm.Find the position of an image when the object is at a distance 20cm from the lens.

According to the question;

Focal length (f) = - 30 cm


Object distance (u) = - 20 cm.


Image distance = v.


By lens formula;



⇒


⇒


⇒


⇒ V = - 12 cm.


Hence image is formed at distance of 12 cm from the lens.


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