Which type of mirror is commonly used as a rear view mirror in vehicles to provide a wider field of view?

Introduction / Context:
Rear view mirrors in cars, buses and other vehicles are essential for safe driving because they allow the driver to see traffic behind and to the sides of the vehicle. The choice of mirror type affects how much of the scene the driver can see and how large or small objects appear. This question asks which type of mirror is most suitable and therefore commonly used as a rear view mirror, given the need for a wide field of view.

Given Data / Assumptions:
- There are three common mirror types in basic optics: plane, concave and convex.
- Rear view mirrors must show a wide area behind and to the side of the vehicle.
- Drivers need an image that is upright and reasonably clear, even if the size is reduced.
- Safety and practicality are more important than producing life sized images.

Concept / Approach:
A plane mirror provides an image of the same size as the object and preserves distances, but its field of view is limited by its size. Concave mirrors can magnify images when objects are within focal length, but they can also invert images and give a very limited field of view, which is not suitable for rear view mirrors in vehicles. Convex mirrors, however, produce virtual, upright, diminished images and allow a much wider field of view because they curve outward. This means drivers can see more of the road behind and to the side, even though the images appear smaller. For this reason, convex mirrors are the standard choice for rear view mirrors on the passenger side and often for external mirrors in general.

Step-by-Step Solution:
Step 1: Describe a plane mirror: it produces an upright virtual image of the same size as the object and has a limited field of view. Step 2: Describe a concave mirror: depending on the object position, it can produce magnified or inverted images and tends to have a narrow field of view. Step 3: Describe a convex mirror: it always produces a virtual, upright, reduced size image and provides a wide field of view. Step 4: Rear view mirrors need to cover as much of the area behind and beside the vehicle as possible for safety. Step 5: A convex mirror achieves this by spreading out the reflected rays and compressing a wide area into a smaller image. Step 6: Conclude that the convex mirror is the preferred and commonly used type for vehicle rear view mirrors.

Verification / Alternative check:
In many vehicles, you can read a warning printed on the side mirror that says objects in the mirror are closer than they appear. This is a direct consequence of the convex mirror producing reduced size images. Observing the curved outward shape of the mirror also confirms that it is convex. Plane and concave mirrors do not show this characteristic behaviour in standard car mirrors.

Why Other Options Are Wrong:
Concave mirror: Its field of view is limited, and it can form inverted images of distant objects, which would be confusing and unsafe for drivers.
Plane mirror: While it gives correctly sized images, the field of view is too narrow compared with what a convex mirror can provide in the same physical space.
Any type of mirror can be used equally well: This is incorrect because different mirror types produce different image properties, and only the convex mirror offers the needed combination of wide field and upright image.

Common Pitfalls:
A common confusion is between the inside and outside curvature of mirrors. Learners sometimes mix up concave and convex by their shape. Remember that a convex mirror bulges outward like the outside of a sphere and spreads light rays apart, giving a wide view. Associating convex mirrors with rear view mirrors and shop security mirrors helps reinforce this concept.

Final Answer:
The rear view mirrors in vehicles commonly use a convex mirror to provide a wide field of view.