Solution

Given- f= 18 cm, u= -12 cm, h1(height of the object) = 2.4 cm Applying lens formula, 1/f =1/v-1/u 1/v = 1/18 + 1/-12 = 2 - 3/36=-1/36 v=-36 cm. m(magnification) = h2(image height)/h1(object height) = v/u h2/2.4 = (-36)/-12=3 h2=7.2 cm. Hence, the image formed is virtual & erect, 36 cm from the lens and large in size (7.2 cm).