9709 P42 - Jun 2019 - Q5
3960
Two particles A and B, of masses 0.4 kg and 0.2 kg respectively, are connected by a light inextensible string which passes over a fixed smooth pulley. Both A and B are 0.5 m above the ground. The particles hang vertically (see diagram). The particles are released from rest. In the subsequent motion B does not reach the pulley and A remains at rest after reaching the ground.
(i) For the motion before A reaches the ground, show that the magnitude of the acceleration of each particle is \(\frac{10}{3} \text{ m s}^{-2}\) and find the tension in the string. [4]
(ii) Find the maximum height of B above the ground. [4]
