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SAI INTERNATIONAL SCHOOL
                                                         Class 7
                                                     Lesson Notes
                                                   Subject-Physics
                                     CH: Light and Associated Phenomena
                                           Subtopic- Laws of Reflection


               Laws of Reflection
               There are two laws of reflection
                              The angle of incidence is always equal to the angle of reflection.
                              The incident ray, the reflected ray and the normal at the point of
                                 incidence lie on the same plane.


















                                  i= angle of incidence and r= angle of reflection

               Terms Used in Reflection of Light
               Incident Ray: The ray of light that falls on the surface of the reflecting material or
                        mirror is called the incident ray.


               Reflected Ray: The ray which is sent back from the surface is called reflected ray.


               Normal: The line perpendicular to the surface at the point of incidence is called normal.


               Point of Incidence : It is the point at which light ray strikes the surface.


               Angle of Incidence: The angle formed by the incident ray with the normal is called
               angle of incidence.


               Angle of Reflection: The angle formed by the reflected ray is called angle of
               reflection.


               SUGGESTED ACTIVITY: Verify the laws of reflection using plane mirror, paper,
               and a torch, cardboard with a slit. Make the light from torch pass through the slit and fall
               on the mirror. Observe the reflected ray. Keep changing the angle of incidence by
               moving the torch and observe how the angle of reflection changes.
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