Which type of mirrors are commonly used in torches, searchlights and vehicle headlights to get powerful parallel beams of light?

Correct option is C

The correct answer is (c) Concave.

Concave mirrors are commonly used in torches, searchlights, and vehicle headlights to get a powerful parallel beam of light. This type of mirror is curved inward, and when parallel rays of light hit it, they are reflected and converge at a single point, which can then be directed as a strong parallel beam.

Information Booster

• Concave Mirror
  • Light rays parallel to the principal axis converge after reflection, focusing the light into a parallel beam.
  • Commonly used in devices that need focused light, such as headlights and flashlights.
  • Found in optical instruments like telescopes for collecting light.

Additional Knowledge

• Convex Mirror

  • Light rays diverge after reflection.
  • Used in rearview mirrors for wide-angle views but not for focusing light.

• Cylindrical Mirror

  • Curved along one axis, not effective for creating parallel light beams in most applications.

• Bifocal Mirror

  • Contains two focal lengths.
  • Primarily used in eyeglasses for vision correction, not for focusing light in optical devices.