Question

From a building, two balls A and B are thrown such that A is thrown upwards and B downwards (both vertically). If  v_A and v_B are their respective velocities on reaching the ground, then

(a) v_B  > v_A
(b) v_A = v_B
(c) v_A > v_B
(d) their velocities depend on their masses

Answer 1

Correct option (b) v_A = v_B
Explanation :

'From conservation of energy,
Potential energy at height h = Kinetic energy at ground

Therefore, at height h PE of ball A = m_Agh

Note In this question, it is not mentioned that magnitude of thrown velocity of both balls are same which is assumed in solution.