An object is placed at 10 cm from a convex lens of focal length 12 cm. Find the position, nature and magnification of the image.

Explanation

Data : Convex lens `, u=-10 cm`, `f=12 cm , v=?`
`1/f=1/v-1/u therefore 1/v=1/f+1/u`
`therefore 1/v =(1)/(12cm)+(1)/((-10cm))`
`=-((1)/(10cm)-(1)/(12cm))`
`=-((6-5)/(60cm))=-(1)/(60cm)`
`therefore v=-60 cm ` it is negative
The image is formed at 60 cm from the lens and on the same side of the lens relative ot the object . It is virtual , erect and enlarged.