1.

The size of the image, if an object of 2.5 m height is placed at a distance of 10 cm from a concave mirror is:(Take radius of curvature of concave mirror = 30 cm)

Answer»
Height of object = h = +2.5 m = 250 cm

Object distance = U = -10cm

R = -30 cm

Focal LENGTH = R/2 = -15 cm

Image distance = v = ?

Height of image = h' = ?

APPLYING MIRROR formula,

1/f = 1/v + 1/u

1/v = 1/f - 1/u
      =-1/15  + 1/10
     = -2+3/30
     =-1/30

v = -30 cm

We know that ,

MAGNIFICATION = m

m = -v/u
    = -(-30)/-10
   = -3

Also,

m = h'/h
-3 = h'/250
h' = -750 cm

Size of the image = h' = 750 cm 

The image is 750 cm or 7.5 metres high



Discussion

No Comment Found

Related InterviewSolutions