A convex mirror is preferred over a plane mirror in vehicles primarily because it offers a wider field of view, which is crucial for safety.
Enhanced Field of View
The fundamental reason for using convex mirrors as side mirrors in vehicles is their ability to reflect a much larger area compared to flat (plane) mirrors.
- Convex Mirror: Bends outwards, causing light rays to diverge. This divergence allows the mirror to capture and reflect images from a wider angle.
- Plane Mirror: Is flat, reflecting light rays without changing their relative direction. This limits the reflected area to roughly the same size and angle as the mirror itself.
As the reference states, "A convex mirror has a wider field of view than a flat one, which can only reflect the area right in front of it."
Increased Awareness for the Driver
This wider field of view translates directly into increased awareness for the driver. Being able to see more of the road and surrounding areas, particularly in the lanes beside and behind the vehicle, helps reduce blind spots.
The reference highlights this benefit: "With a wider field of view, the driver has more information about the area to the right of the car." This extra information is vital for making safe decisions when changing lanes, merging into traffic, or parking.
Practical Advantages
While a convex mirror makes objects appear smaller and farther away than they actually are (leading to the common warning "Objects in mirror are closer than they appear"), the safety advantage of seeing a broader area outweighs this distortion for vehicle side mirrors.
In summary, the primary reason a convex mirror is preferred over a plane mirror in vehicles is its inherent optical property to provide a significantly wider field of view, giving the driver more comprehensive visual information about their surroundings for enhanced safety.
