Q69. Mention against each of the following whether regular or diffused reflection will take place when a beam of light strikes. Justify your answer in each case.
(a) Polished wooden table (b) Chalk powder (c) Cardboard surface (d) Marble floor with water spread over it (e) Mirror (f) Piece of paper
Q70. Describe the construction of a kaleidoscope.
Q71. Describe an activity to show that the incident ray, the reflected ray and the normal at the point of incidence lie in the same plane.