Question

In torches, search lights and headlights of vehicles the bulb is placed

• A. Between the pole and the focus of
• B. Very near to the focus of the reflector
• C. Between the focus and the center of curvature of the reflector.
• D. At the center of curvature of the reflector

Answer 1

The correct option is B

Very near to the focus of the reflector

Explanation for correct option:

Option (B),

Concave mirrors are used in headlights and torches. Bulbs are placed nearer to the focus of the reflector to form a parallel beam of lights which helps to see a long distance.

Explanation for incorrect options:

Option (A),

Parallel beams of light are not produced from the light source that is placed between the pole and the focus.

Option (C ),

The light source between focus and center of curvature will form the image beyond ‘C’.

Option (D),

At point ‘C’ the object will form the image that is inverted and real.

Hence, option B is the correct answer.