LIGHT
The source of energy which gives sensation of sight is called light.
Reflection of light:
• The phenomenon of bouncing back of light in same medium
from any reflecting surface is called reflection of light.
•Incident ray: the light ray which falls on any reflecting
surface.
•Reflected ray: the light ray which comes back in the same
medium after reflection.
•Reflecting surface: the surface on which light ray falls and
reflection happens.
•Point of incidence: the point at which incidence ray strikes
the reflecting surface.
•Angle of incidence: the angle between incident ray and
normal ray.
•Normal: the perpendicular line drawn at point of incidence on
reflecting surface.
•Angle of reflection: the angle between reflected ray and
normal ray.
LAWS OF REFLECTION:
• The incident ray, reflected ray and normal at same point of
incidence on reflecting surface lie on the same plane.
• The angle of incidence (i) and the angle of reflection (r) are
always equal.
i.e. ∠i=∠r.
