Question

an object placed at a distance of 30 cm infront of convex mirror and focal length of 15cm. write the four charateristics of image formed by the convex mirror

Answer 1

Here, as the focus is at 15 cm, the centre of curvature is at 30cm.
Henceforth the object is on the centre of curvature.
Therefore the characteristics of the image:
Real
Inverted
Of same size

Answer 2

HI !

Object distance = u = -30 cm
Focal length = f = +15 cm
Image distance = v = ?

Applying mirror formula,

1/v + 1/u = /f

1/v = 1/f - 1/u

1/v = 1/15 - (-1/30)

1/v = 1/15 + 1/30

1/v = 2+1/30

1/v = 3/30

v = 30/3

v = +10 cm

magnification = m

m= -v/u
   = -(10/-30)
   = 10/30
   = 1/3



(1) The image formed is at a distance of 10 cm behind the mirror.
(2) The image formed is virtual and erect
(3) Image is formed between the Pole and the Principal Focus
(4) The image formed is 1/3rd of the real object(in height/size)