A student holding a mirror in his hand, directed the reflecting surface of the mirror

Light (10)

A student holding a mirror in his hand, directed the reflecting surface of the mirror towards the Sun. He then directed the reflected light on to a sheet of paper held close to the mirror.

  1. What should he do to burn the paper ?
  2. Which type of mirror does he have ?
  3. Will he be able to determine the approximate value of focal length of this mirror from this activity ? Give reason and draw ray diagram to justify your answer in this case.

Answer

  1. Move the mirror/paper to focus the rays at one point
  2. Concave mirror
  3. Yes, distance between mirror and focal point gives approximate focal length.

  • Exam Year: 2019