Final answer:
The adjustment of the car's side mirrors to not show the vehicle sides is to prevent blind spots. This is related to optics in Physics, where directional light beams and the effects of lenses on viewing angles are studied. Mirrors are adjusted similar to how headlight beams are focused for better visibility.
Step-by-step explanation:
When adjusting the vehicle's side mirrors to the setting described, the driver is practicing a method intended to reduce blind spots by positioning the mirrors to not show the sides of the car. Instead, this adjustment extends the field of view further out, which helps the driver monitor adjacent lanes. This mirror setting aligns with the information provided about directional beams as with headlights in Figures 25.47 and 25.46, where mirrors are used to focus and direct light for better visibility.
Additionally, Figures 25.36, 25.35, and 25.37 illustrate how a converging or diverging lens affects the appearance of a viewed object, suggesting that understanding optical principles is essential for automotive applications, such as designing mirrors for optimal viewing. The reminder that only half a lens is necessary to form an image, albeit a fainter one, lays the foundation for why precise mirror adjustment is so effective even though the car body is no longer visible.