1. The problem statement, all variables and given/known data 2. Relevant equations 3. The attempt at a solution The question says block B has negligible mass ,which means particle will be effectively in free fall i.e acceleration would be 'g' . But then it is given a horizontal velocity i.e it has centripetal acceleration ac about the pulley v2/r . The forces acting on the particle are Mg and tension T . So, Mg -T = M(√(g2+ac2)) I am really clueless with this problem . Please help me .