Name the type of mirror used in the following situations. (a) Headlights of a car. (b) Side/rear-view mirror of a vehicle. (c) Solar furnace. Support your answer with reason.
Concave mirror is used in the headlights of a car. When the light source (bulb) is placed at the principal focus of a concave mirror, the reflected rays become parallel to each other. This produces a powerful, parallel beam of light that travels straight ahead and effectively illuminates the road over a long distance.
Convex mirror is used as the side/rear-view mirror in vehicles. Convex mirrors are preferred because they always give an erect, though diminished, image. They have a wider field of view as they are curved outwards, enabling the driver to view a much larger area of traffic behind than would be possible with a plane mirror. This facilitates safe driving.
Concave mirror is used in a solar furnace. A concave mirror has the property of converging parallel rays of light to its principal focus. When sunlight (parallel rays from infinity) falls on a large concave mirror, it gets concentrated at the focus, producing intense heat. This heat energy can be harnessed for various applications.
Explanation
This question tests understanding of practical applications of spherical mirrors. The context explicitly states that convex mirrors are used as rear-view mirrors because they provide erect images and wider field of view. For headlights and solar furnaces, concave mirrors are used because of their converging properties - they can produce parallel beams (when source is at focus) or concentrate light (when parallel rays fall on them).