The Law Of Reflection Of Light
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The Law Of Reflection Of Light The ray model of light is an established simple assumption about the motion of light in the macro-realm (non-quantum realm). The ray model of light assumes that light travels in straight-line paths; light rays from luminous objects spread out in all directions and an image is formed when the light rays leaving the object from the same point meet. The ray model of light does not disrupt the particle-wave nature of light.

(a) Prove the law of reflection of light which states that the angle of incidence of a ray of light is equal to the angle of reflection.
(b) Indicate the position of the mirror image of a point O (figure 21.1) which is in front of a plane mirror.

The strings:

S7P4A41 (Motion - Linear).

The math:
Pj Problem of Interest is of type motion (linear). The ray model of light implies linear motion of light. (a) Consider figure 21.1. OM is the light ray, KQ the reflecting surface, MO' the reflected ray and PM is a the normal to KQ.
Construct PO' such that PO' is parallel and equal to MO. Construct OP such that OP is parallel and equal to MO'.
So, OMO'P is a parallelogram and PM one of its diagonal.
So, <1 = <2 (bisection of angle by diagonal)
So, <4 = <3. since PM is perpendicular to KQ.
Generally, <4 is considered to be the angle of incidence of the light ray OM while < 3 is considered to be the angle of reflection of the reflected ray. Some choose <1 as the angle of incidence and <2 as the angle of reflection. No difference. It depends on the reference line (normal or horizontal).
So, angle of incidence = angle of reflection. Euclid is credited with the discovery of this law of reflection of light.

(b) The mirror image of O is on a perpendicular from O to the mirror KQ and as far behind the mirror as O is in front (figure 21.1).
So, the image of O is at N, where OL = LN.

Math The Universe is composed of matter and radiant energy. Matter is any kind of mass-energy that moves with velocities less than the velocity of light. Radiant energy is any kind of mass-energy that moves with the velocity of light.
Periodic Table
Composition And Structure Of Matter
How Matter Gets Composed
How Matter Gets Composed (2)
Molecular Structure Of Matter
Molecular Shapes: Bond Length, Bond Angle
Molecular Shapes: Valence Shell Electron Pair Repulsion
Molecular Shapes: Orbital Hybridization
Molecular Shapes: Sigma Bonds Pi Bonds
Molecular Shapes: Non ABn Molecules
Molecular Orbital Theory
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Blessed are they that have not seen, and yet have believed. John 20:29