See image — AITS & Test Series Chemistry Question

💡 Solution & Explanation

When incident ray is fixed the angular velocity of reflected ray becomes twice in the same sense as that of reflected ray. After t = 15 sec, the mirror rotates 15° then reflected ray rotates 30° in the same sense. In ABC, 3 cos60 r  Where  = rad / sec.r 6m 180   Then, there are two components of velocity of spot on the screen. (a) radial component which increase the length of r i.e., s dr V sin60 dt  (b) perpendicular component normal 3m Q 60o incident ray Plane mirror screen 60o 90o 2r C Vs 30o r = 6m 60o 30o 30o s s s 1 2 V cos60 V 2 6 V m / s 2 180 15               