See image — AITS & Test Series Chemistry Question

💡 Solution & Explanation

Let x be the distance of axis of rotation from the top of sphere A (downward). Since angular velocity of the top and bottom point of sphere A will be same, therefore, 30 10 (2R ) x x    1v =30 2 v =10  A x 30 10 20 x x    x = 15  Distance from ground = 2R + (2R  x) = 20 + 5 = 25 cm