Which kind of mirror is used in the headlight of a motor car and why?

An object is placed at the following distances from a concave mirror of focal length $20 \mathrm{cm}$.

(a) $10 \mathrm{cm}$         (b) $30 \mathrm{cm}$           (c) $44 \mathrm{cm}$         (d) $40 \mathrm{cm}$

Which position of the object will produce

(i) virtual image

(ii) a diminished image

(iii) an enlarged image

(iv) an image of same size.

Copy the figure in your answer book and show the direction of light after reflection showing the angle of incidence and angle of reflection.

Name the mirror that 

(a) can give real as well as virtual image of an object.

(b) will always give virtual image of same size of an object.

(c) will always give virtual and diminished image of an object.

(d) is used by a doctor in examining teeth.