Question

Find the nature, position and magnification of the images formed by a convex lens of focal length 0.20 m if the object is placed at a distance of:  

 0.25 m 

Answer 1

u = -25 cm
          f = 20 cm  

⇒`1/f=1/v-1/u` 

⇒`1/20=1/v-1/-25` 

⇒`1/v=1/200-1/25`  

⇒`1/v=(5-4)/100`  

⇒`1/v=1/100`   

⇒`v=100` cm 

The image will be formed at a distance of 100 cm behind the mirrror.Magnification, 

⇒`m=v/u` 

⇒`m=100/-25`

  `m=-4`  

Magnification is negative, which means the image is real and inverted.