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 : u=−10 cm f=−5 cm ho=6 cm
Using lens formula : 1v−1u=1f
∴ 1v−1(−10)=1−5
⟹v=−103=−3.33 cm (- sign shows that image is virtual)
Also m=hiho=vu
∴ hi6=−103−10
⟹hi=+2 cm (+ sign shows that image is erect)