Uses of Concave Mirrors:
1. Shaving mirror:
A concave mirror is used as a shaving or make-up mirror because it forms erect and enlarged image of the face when it is held closer to the face.
2. As head mirror:
E.N.T. specialists use a concave mirror on their forehead. The light from a lamp after reflection from the mirror is focused into the throat, ear or nose of the patient making the affected part more visible.
3. In ophthalmoscope:
It consists of a concave mirror with a small hole at its centre. The doctor looks through the hole from behind the mirror while a beam of light from a lamp reflected from it is directed into the pupil of patient’s eye which makes the retina visible.
4. In headlights:
Concave mirrors are used as reflectors in headlights of motor vehicles, railway engines, torch lights, etc. The source is placed at the focus of the concave mirror. The light rays after reflection travel over a large distance as a parallel beam of high intensity.
5. In astronomical telescopes:
A concave mirror of large diameter (5 m or more) is used as objective in an astronomical telescope.
It collects light from the sky and makes visible even those faint stars which cannot be seen with naked eye.
6. In solar furnaces:
Large concave mirrors are used to concentrate sunlight to produce heat in solar furnace.
Uses of Convex Mirrors:
Drivers use convex mirror as a rear-view mirror in automobiles because of the following two reasons:
1. A convex mirror always forms an erect, virtual and diminished image of an object placed anywhere in front of it.
2. A convex mirror has a wider field of view than a plane mirror of the same size
Thus convex mirrors enable the driver to view much larger traffic behind him than would be possible with a plane mirror.
The main disadvantage of a convex mirror is that it does not give the correct distance and the speed of the vehicle approaching from behind.