Question

Q. 1. Solve the following examples :
1. An object is placed at a distance of 20 cm in
front of a convex mirror having focal length
0.3 m. Find the position, nature and magni-
fication of the image formed by the mirror.​

Answer 1

Answer:

1)  u=-20

f=+30cm

1/f=1/v+1/u

1/30=1/v+(-1/20)

1/30+1/20=1/v

v=6/5cm    

m=-v/u

m=-6/5/-20

m=3/50cm

2)  To find: Image distance, v

From mirror formula :

1/v+1/u=1/f

1/v-1/10=1/15

1/v=1/15+1/10

=25/150

v=6cm

Hence image will be formed 6 cm beyond the mirror, i.e virtual magnification.

m=-v/u

 =-6/-10

 =0.6

Hence it will be erect and diminished.