Question

An object 4 cm is placed at a distance of 27 cm in front of a convex lens of focal length 28 cm . Find position , nature , and size of the image formed .

Answer 1

Explanation:

h1= 4cm, f= 28cm, u= 27cm

v= ? ,h2= ?

1/v= 1/f-1/u = 1/28 -1/27

=> v= (28×27) / (27-28) = - 756 cm

=> v/u = h2/h1

=> h2= vh1/u= 756×4/27 = 112 cm

therefore image is virtual, erect ,756 cm behind the lens and 112 cm length.