Question

An object is 12.2 cm from the surface of a reflective spherical Christmas-tree ornament 7.31 cm in diameter.

(a) What is the position of the image? Answer in units of cm.

(b) What is the magnification of the image?

Answer 1

Given

   object distance s = 12.2 cm from the spherical surface of radius of curvature R = -3.655 cm

   image distance s' = ?

   magnification m = ?

from the relation between object distnace , image distance and radius of curvature
  

   1/s + 1/s' = 2/R

   1/s' = -2/R - 1/s
   1/s' = -2/3.655 -1/12.2

   s' = -1.589 cm

the image distane is s' =-1.589 cm

magnification is m = -s'/s = -(-1.589/12.2) = 0.130

image is diminished one (less than size of object)