A convex lens can form a magnified erect as well as magnified inverted image of an object placed in fron of it. Draw ray diagram to justify thisby statement stating the position of the object with respect to the lens in each case. An object of height 4 cm is placed at a distance of 20 cm from a concave lens of focal length 10 cm. Use lens formula to determine the position of the image formed.

A convex lens can form a magnified erect as well as magnified inverted

1.	A convex lens can form a magnified erect as well as magnified inverted image of an object placed in fron of it. Draw ray diagram to justify thisby statement stating the position of the object with respect to the lens in each case. An object of height 4 cm is placed at a distance of 20 cm from a concave lens of focal length 10 cm. Use lens formula to determine the position of the image formed.
Answer» Solution :Convex LENS form magnified erect image when object is PLACED betweenn `F_(1)` and optical centre O. Image formed is virtual, erect and enlarged and on the same side of the lens as the object. Convex lens form magnified inverted image when object is placed at `F_(1)`. Image formed is real, inverted and enlarged at infinity. Given focal length f=+10 cm (concave) OBject distance (u)=-20 cm For concave lens `1/f=1/v-1/u` we GET `1/f+1/u=1/v` `1/(-10)+1/(-20)=1/v` or `=1/10-1/20 ` or `1/v=(-2-1)/20=(-3)/20` `v=-20/3cm` `m=(h_(1))/(h_(0))=v/u` `h_(1)=v/uxxh_(0)` `=(-20)/(3xx-20)xx4=4/3=1.3cm` Image is diminished.