1. A system consists of three masses \(m_1\), \(m_2\) and \(m_3\) connected by a string passing over a pulley P. The mass \(m_1\) hangs freely and \(m_2\) and \(m_3\) are on a rough horizontal table (the coefficient of friction = \(\mu\)).The pulley is frictionless and of negligible mass. The downward acceleration of mass \(m_1\) is (Assume \(m_1\) = \(m_2\) = \(m_3 \) = m)