Question

An object 1.2 cm long is placed at a distance of 12 cm from a diverging mirror of focal length
6 cm. Find the position and size of the image formed.
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Answer 1

Given :

Height of object = 1.2cm

Distance of object = 12cm

Focal length of mirror = 6cm

Type of mirror : convex

To Find :

Position and size of the image.

Solution :

⧪ Focal length of concave mirror is taken negative and that of convex mirror is taken positive$.$

Distance of image can be calculated by using mirror formula which is given by

• 1/u + 1/v = 1/f

u denotes distance of object

v denotes distance of image

f denotes focal length

By substituting the given values;

➠ 1/u + 1/v = 1/f

➠ 1/(-12) + 1/v = 1/6

➠ 1/v = 1/6 + 1/12

➠ 1/v = (2+1)/12

➠ v = 12/3

➠ v = 4 cm

⧪ Size of image :

➝ -v/u = h'/h

• h' : size of image
• h : size of object

➝ -4/(-12) = h'/1.2

➝ 1/3 = h'/1.2

➝ h' = 1.2/3

➝ h' = 0.4 cm