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:   

 0.50 m

Answer 1

 u =-0.50 m = -50 cm
f = 0.20 m = 20 cm
Lens formula: 

`1/f=1/v-1/u` 

⇒`1/20=1/v-1/-50` 

⇒`1/v=1/20-1/50`  

⇒`1/v=(5-2)/100` 

⇒`1/v=3/100` 

⇒`v=100/3` cm 

The image will be at a distance of 33.3 cm on the right side of the mirror

magnification   `m=v/u` 

`m=33.3/-50` 

`m=-0.66` 

magnification is negative therefore image will be real and inverted.