♥Understanding reflection of light♥

THE LAWS OF REFLECTION
•The angle of incidence i is equal to the angle of reflection r (θi=θr)

•The incident ray, the reflected ray and the normal all lie in the same plane at the point of incident.

Reflection of light on a plane mirror

characteristic of the image
-laterally inverted
-same size
-same distance
-upright
-virtual

Types of reflection
•regular reflection

-smooth  and flat surface

-all parallel rays are reflected in the same direction

•irregular reflection

-rough and matt surface

-all parallel are randomly reflected in different direction 

Reflection of light on curve mirror
•concave mirror&convex mirror

Distance u	Ray diagram	Characteristic of image
concave u>2f		-real                        -inverted                     -diminished                     -infront of      the mirror
u=2f		-real   -inverted -same size  -infront of  the mirror
2f>u>f		-real -inverted -magnified -infront of  the mirror
u=f		image infinity
u<f		-virtual -upright -magnified -behind of  the mirror
convex u>2f		-virtual -upright -diminished  -behind of  the mirror
2f>u>f		-virtual -upright -diminished -behind of  the mirror

Application of reflection of light

Microscope 

-use a mirror to reflect light to the specimen under the microscope 

Astronomical telescope

-use a large parabolic mirror to gather dim light from distantars. A plane mirror is used to reflect the image to the eyepiece