Param Himalaya - परम हिमालय

Definition and laws of Reflection of light.  When rays of light are incident on an opaque smooth polished surface , they are bounced back in the same medium . This phenomenon of bouncing back of rays of light in the same medium is called reflection of light.  Some useful terms associated with of reflection of light :  1. Point of incidence : The point on the reflecting surface at which a ray of light strikes at the time of reflection is known as the point of incidence . In above diagram , O is at the point of incidence. 2. Reflecting Surface : The reflecting surface is the surface from which the light is reflected . In the above diagram X'X is the reflecting Surface. 3. Normal : A perpendicular drawn on the reflecting surface at the point of incidence is called the normal. in above diagram , ON is the normal. 4. Reflected Ray : The ray of light reflected from the reflecting surface from the point of incidence is known as the reflected Ray , in the above diagram , OR is...

Light : Type of Medium For the Propagation of Light Light travels along a straight line. The path of light changes only when the medium changes or when it's strikes with any other surface. Transparent Medium:  A medium which allow the passage of light through it freely is known as a transparent Medium . Example : Water , Glass and Glycerin are Transparent. Opaque Medium  :  A medium that blocks light from travelling through it is called opaque. Example : wood , metals , bricks . Translucent Medium :   A medium in which light can travel partially, but it's intensity reduces rapidly are called translucent. Example : oil