Section 11.2 The Law of Reflection
Subsubsection Key Ideas
When a ray of light encounters an object, the light is usually either absorbed, scattered, or reflected.
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Absorbed light will no longer move through the physical world.
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Scattered light will emerge in all directions, causing the object to act as a new point source of light.
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Reflected light will move in a single new direction given by the Law of Reflection. Objects like mirrors typically reflect most incident light.
Principle 11.2.2. The Law of Reflection.
For a ray of light incident on a flat mirror, the reflected angle \(\theta_{r}\) is equal to the incident angle \(\theta_{i}\text{,}\) both measured from the line normal to the surface:
\begin{equation*}
\theta_{r} = \theta_{i}
\end{equation*}
Subsubsection Activities
Activity 11.2.1. Analogies for Reflection of Light.
Are there any other objects in your personal experience that “reflect” or “bounce” in a way that reminds you of how light behaves? Choose one and briefly discuss any similarities or differences you see between the two situations.
