•Always travels in a straight line. This is

the rectilinear propagation of light

•Speed = 300,000 m/s

•Travels in the form of wavelength

When light hits any surface it may

1. Bounce back

2. Absorb

3. Pass through

When light hits any surface and

bounces back ,it is called reflection .

There may be two types of reflection :

Diffuse reflection

Clear reflection

From a rough

surface

The rays may go in

any direction

Image generally

not formed

The surface will

not act as a mirror

From smooth and

shiny surface

An image is

formed

The surface will

act as a mirror

Real : An image which forms on a screen

Virtual : An image which is formed inside

the mirror

Erect :straight

Inverted : an image which is not straight

Lateral inversion : when left side appears

on right and right appears on left side

•NATURE OF THE IMAGE :

•Laterally inverted

•Erect

•Same size

•Distance between object and the mirror is same as the distance

between the image and the mirror

•Virtual

surface normal

same

angleincident rayexit ray

reflected ray

•Angle of incidence = Angle of reflection

•Normal , incident ray and the reflected ray

, they all lie on the same plane.

Parallel rays

Reflected rays

Real

Focus

Focal length = +

Forms real, inverted,

Reduced or enlarged

Image. Also forms

Virtual, erect,

Enlarged images.

OBJECT IMAGE NATURE

BETWEEN P AND

F

BEHIND THE

MIRROR

ERECT,VIRTUAL,ENLARGED

AT F NO IMAGE -

BETWEEN C

AND F

BEYOND C INVERTED,REAL,LARGE

AT C AT C INVERTED,SAME SIZE ,REAL

BEYOND C BETWEEN C AND

F

INVERTED, REAL,SMALL

Parallel rays

Reflected rays

Virtual focus

Focal length = -Forms only virtual,

erect, reduced

images between

the virtual focus

and the mirror.

OBJECT IMAGE NATUREBETWEEN P AND F BETWEEN P AND

F(INSIDE THE

MIRROR)

VIRTUAL,ERECT,SMALL

AT F BETWEEN P AND

F(INSIDE THE

MIRROR)

VIRTUAL,ERECT,SMALL

BETWEEN C AND F BETWEEN P AND

F(INSIDE THE

MIRROR)

VIRTUAL,ERECT,SMALL

AT C BETWEEN P AND

F(INSIDE THE

MIRROR)

VIRTUAL,ERECT,SMALL

BEYOND C BETWEEN P AND

F(INSIDE THE

MIRROR)

VIRTUAL,ERECT,SMALL

focus (f)focus (f) 2 f2 f

x x x x

Parallel ray

Passes thru

The focus

Refracts parallel

To principal axis

A ray thru the

Center of the

lenses

Remains

unbent

OBJECT IMAGE NATURE

BETWEEN P AND

F

BEHIND THE

MIRROR

ERECT,VIRTUAL,ENLARGED

AT F NO IMAGE -

BETWEEN C

AND F

BEYOND C INVERTED,REAL,LARGE

AT C AT C INVERTED,SAME SIZE ,REAL

BEYOND C BETWEEN C AND

F

INVERTED, REAL,SMALL

f2 f f 2 f

Parallel ray

Image is:

Virtual

Erect

Reduced

Appears on same

Side as object

OBJECT IMAGE NATUREBETWEEN P AND F BETWEEN P AND

F(INSIDE THE

MIRROR)

VIRTUAL,ERECT,SMALL

AT F BETWEEN P AND

F(INSIDE THE

MIRROR)

VIRTUAL,ERECT,SMALL

BETWEEN C AND F BETWEEN P AND

F(INSIDE THE

MIRROR)

VIRTUAL,ERECT,SMALL

AT C BETWEEN P AND

F(INSIDE THE

MIRROR)

VIRTUAL,ERECT,SMALL

BEYOND C BETWEEN P AND

F(INSIDE THE

MIRROR)

VIRTUAL,ERECT,SMALL