Two particles A and B have masses 5 m and km respectively, where k < 5. The particles are connected by a light inextensible string which passes over a smooth light fixed pulley. The system is held at rest with the string taut, the hanging parts of the string vertical and with A and B at the same height above a horizontal plane, as shown in the following figure. The system is released from rest. After release, A descends with celeration (1/4)g Find the tension in the string as A descends.