A diverging lens has a focal length of -32 cm. An object is placed 19 cm in front of thiis lens.

Question

calculate

a. the image distance

b. magnification

is the image a

c. real or virtual

d. upright or inverted

e. enlarged or reduced?

Answer 1

u = object distance

v = image distance

f = focal  length

m = magnification

1 / u + 1 / v = 1 / f

1 / 19 + 1 / v = 1 / (- 32)

v = - 11.9 cm.

Image distance 11.9 cm.

(b)

m = v / u

= - 11.9 / 19

= - 0.627.

Magnification 0.627.

(c)

Virtual.

(d)

Upright.

(e)

Reduced.