A 200cmtall object is 350 cm in front of a converting lens t

A 2.00-cm-tall object is 35.0 cm in front of a converting lens that has a focal length of 20.0 cm. Where is the image formed, what type of image is it, and what is the image height?

Solution

object distance = s = 35 cm

focal length f = +20 cm

from the lens equation

1/s + 1/s\' = 1/f

1/35 + 1/s\' = 1/20

image distance = s\' +46.7 cm

image distance is positive , so the image is positive

magnitfication = m = -s\'/s = -46.7/35 = -1.334

the image is inverted

magnification = m = hi/ho

height of the image = hi = m*ho = 1.334*2 = 2.67 cm

46.7 cm beind the lens , real and invrted 2.67 cm tall

OPTION (C)