2. Magnification
• Magnification is the ratio of image height to object height.
• 𝑚 =
ℎ𝑖
ℎ𝑜
• The magnitude of m shows whether the object is enlarged or
diminished.
• m= 1 same m >1 enlarged m <1 - diminished
• The sign of m shows whether the image is erect or inverted.
3. Magnification and nature of image
magnificati
on
m
Enlarged /
diminished
Erect/
Inverted
Real/Virtual Possible
mirror
2 E E V CONCAVE
0.5 D E V CONVEX
-3 E I R CONCAVE
-1/3 D I R CONCAVE
-5/2 E I R CONCAVE
3/5 D E V CONVEX
1 SAME SIZE E V PLANE
-1 SAME SIZE I R CONCAVE
4. An object is placed at a distance 15 cm in front of
a concave mirror of focal length 10 cm.Find the
position and nature of image.
5.
6. An object of height 2 cm is placed at a distance 25
cm in front of a concave mirror of focal length 10
cm.Find the position , size and nature of image.
7.
8.
9. An object is placed at a distance 10 cm in front of
a concave mirror of focal length 15 cm.Find the
position and nature of image.
10. An object is placed at a distance 15 cm in front of
a convex mirror of radius of curvature 20 cm.Find
the position and nature of image.
11. An object of height 2 cm is placed at a distance 25
cm in front of a convex mirror of radius of
curvature 20 cm.Find the position and nature of
image.
12.
13. At what distance from a concave mirror of focal
length 15 cm will you place an object to get a 3
times magnified a) real image b) Virtual image
14.
15.
16. At what distance from a concave mirror of
focal length 20 cm will you place a screen to
get an image half the size of object?
