A 5 cm tall object is placed fraction to the principle axis of a convex lens of focal length 20 cm . The distance of the object from the lens is 30 cm. Find the (i) position, (ii) Nature, (iii) Size of the image formed. Given Object size , h_(0) =5 cm Object size , h_1 = 5cm Object distance , u=-30 cm Focal length of convex lens , f= 20 cm To find : size of image h_1 = ? Nature of image = ? Position of image = ?

A 5 cm tall object is placed fraction to the principle axis of a conve

1.	A 5 cm tall object is placed fraction to the principle axis of a convex lens of focal length 20 cm . The distance of the object from the lens is 30 cm. Find the (i) position, (ii) Nature, (iii) Size of the image formed. Given Object size , h_(0) =5 cm Object size , h_1 = 5cm Object distance , u=-30 cm Focal length of convex lens , f= 20 cm To find : size of image h_1 = ? Nature of image = ? Position of image = ?
Answer» Solution :`1/f = 1/v -1/u ` `1/v = 1/u + 1/f` `=(-1)/(30) +(1)/(20) =(-2 + 3)/(60)` (or) `1/v =1/(60) implies v =60 cm` Magnification =`("height of the image SIZE")/("height of the object")` `=(h_(2))/(h_(1))` `m=(h_(i))/(h_(o)) implies v/u =(60)/(-30)=-2` `therefore h_(2) = h_(1) xx (-2) = 5XX(-2) = 5xx (-2) =-10 cm`. (i) The image is real, inverted and magnified. (II) Size of the image , `h_2 =-10 cm`