Question

A diverging lens has a focal length of magnitude 24.8 cm.

(a) Locate the images for each of the following object distances.
49.6 cm

distance______	cm

distance24.8 cm _________

distance at 12.4cm_____

(d) Find the magnification for the object at distance 49.6 cm.
  


Find the magnification for the object at distance 24.8 cm.


Find the magnification for the object at distance 12.4 cm.

Answer 1

here,

focal length , f = - 24.8 cm

a)

for object distance , do = 49.6 cm

let the image distance be di

using the lens formula

1/f = 1/di + 1/do

- 1/24.8 = 1/di + 1/49.6

solving for di

di = - 18.1 cm

for object distance , do = 24.8 cm

let the image distance be di

using the lens formula

1/f = 1/di + 1/do

- 1/24.8 = 1/di + 1/24.8

solving for di

di = - 12.4 cm

for object distance , do = 12.4 cm

let the image distance be di

using the lens formula

1/f = 1/di + 1/do

- 1/24.8 = 1/di + 1/12.4

solving for di

di = - 8.27 cm

b)

the magnification for the object at distance 49.6 cm , m = - (- 18.1/49.6) = 0.36

the magnification for the object at distance 24.8 cm , m = - (- 12.4/24.8) = 0.5

the magnification for the object at distance 12.4 cm , m = - (- 8.27 / 12.4) = 0.67