Final answer:
The question references the study of optics in Physics, where mirrors are used to trap light and form a directional beam as can be seen in vehicle headlights.
Step-by-step explanation:
The discussion of mirrors and the formation of a directional beam of light, as described in Figures 25.47 and 25.46, pertains to the field of Physics, specifically the study of optics. When inside and left-side rearview mirrors are mentioned in the context of the light being trapped by two mirrors to form a directional beam, it resembles the mechanism of a headlight.
In optics, this is related to the laws of reflection where light rays are redirected in a specific direction to improve visibility. This principle is utilized in vehicle headlights where the light from a bulb is reflected by mirrored surfaces to form a concentrated beam, enhancing the range and focus of the light emitted.