This document discusses virtual and real images formed by mirrors. Virtual images cannot be projected onto a screen and are always on the opposite side of the mirror from the object. Real images can be projected onto a screen and are on the same side of the mirror as the object. Concave mirrors form real, inverted images between the focal point and center of curvature for objects beyond the center of curvature. Ray diagrams are used to determine the nature and position of images formed by concave mirrors depending on the object's position relative to the focal point and center of curvature. The mirror equation can also be used to calculate the position of images.

2. Virtual Images
Virtual Images are basically images which cannot be
visually projected on a screen.
If this box gave off
light, we could project
an image of this box on
to a screen provided
the screen was on the
SAME SIDE as the box.
You would not be able to project the image of
the vase or your face in a mirror on a screen,
therefore it is a virtual image.
CONCLUSION: VIRTUAL IMAGES are ALWAYS on the OPPOSITE
side of the mirror relative to the object.

3. Real Image
Real Images are ones you can project on to a screen.
For MIRRORS they always appear on the SAME SIDE of the
mirror as the object.
The characteristics of
the image, however,
may be different from
object
the original object.
These
characteristics
are:
image
•SIZE
(reduced,
enlarged, same size)
•POSITION (same side,
opposite side)
•ORIENTATION
(right
side up, inverted)

4. Spherical Mirrors – Concave &
Convex
Also called DIVERGING mirror
Also called CONVERGING mirror

5. Converging (Concave) Mirror
Since the mirror is
spherical it technically
has a CENTER OF
CURVATURE, C. The focal
point happens to be
HALF this distance.
We also draw a line through the center
of the mirror and call it the PRINCIPAL
AXIS.

6. (a) Rays parallel to the principal axis
are reflected and they pass through
the principal focus
C
F
P

7. (b) Rays passing through the principal
focus (F) will move parallel to the
principal axis after reflection
C
F
P

8. (c) Ray passing through the centre of
curvature (C) are reflected back along
their own paths because they are
normal to the mirror.
C
F
P

9. Now let us draw a ray diagram for an
object beyond C
I am parallel to the principal
axis. Always draw me first
C
I am reflected parallel to
the principal axis
What is the nature and position of
the image formed?
1) Image is real but inverted.
2) Image is between focus(F)
and center of curvature(C).
Image
I am the
Object
F
P

10. Now let us draw a ray diagram for
an object at C
I am parallel to the principal
axis. Always draw me first
I am the
Object
C
F
I am the image
What is the
nature of
image formed?
1) The image is
real , inverted
and of same
size.
2) The image is
formed at
center of
curvature.
I am reflected parallel to
the principal axis
P

11. Now the object is between C and F
I am parallel to
the principal axis.
I am the
Object
C
F
I am the image now.
What is the
nature of
this image?
1) The
image is
real and
magnified
.
2) The
position
of image
is beyond
center of
curvature
I am reflected parallel to the principal axis
P

12. Now let us draw a ray diagram for
an object at F
I am the
Object
C
F
P

13. Now let us draw a ray diagram for an
object between F and P
What is the
nature of image
formed?
1) The image is
virtual ,
erect and
magnified.
2) The is
formed
behind the
mirror.
I am reflected parallel to
the principal axis
I am the image.
I am the
Object
C
F
P

14. The Sky Mirror in Monte Carlo

15. USES OF CONCAVE MIRROR
Used by females and males in
makeup and shaving by them
respectively. To provide
enlarged and virtual image.
Used in cars to provide strong
parallel beams of light.

16. CONVEX MIRROR

17. Image by convex mirror when object
beyond 2f
Parallel ray
Apparent
Convergence of rays
(f)
Image is:
Virtual
Erect
Reduced
Appears behind the
mirror
2f

18. Image formed by convex mirror when
object is at infinity.
Virtual focus
Parallel rays
Dotted lines
Shows the
Apparent
Ray focus
-
Reflected rays
Focal length =
Forms only virtual,
erect, reduced
images between
the virtual focus
and the mirror.

19. USES OF CONVEX MIRROR
Convex Mirror is used in
the given images
because:1) It help the driver to
see the vehicles
behind them.
2) It covers a large area
as compared to plane
mirror or concave
mirror.
3) It creates erect and
virtual image always

20. The Mirror
Equation
Is there any OTHER way to predict image characteristics besides
the ray diagram? YES!
One way is to use the MIRROR/LENS equation to CALCULATE
the position of the image .
d0 = distance between pole and image
d1= distance between pole and object
1
1
1
f
do
di

21. MAGNIFICATION
Magnification produced by a spherical mirror
gives the relative extent to which the image
of an object is magnified with respect to the
object size.
It is expressed as the ratio of the height of the
image(h2) to the height of the object(h1).
The magnification is also related to the object
distance (u) and image distance(v).
M=h2/h1=-v/u

22. THANK YOU
By:- Kshitiz Rai
10 A