The figure shows the single line diagram of the single machine infinite bus system.

The inertia constant of the synchronous generator . Frequency is 50Hz. Mechanical power is 1pu. The system is operating at the stable equilibrium point with rotor angle  equal to . A three phase short circuit fault occurs at a certain location on one of the circuits of the double circuit transmission line. During fault, electrical power in pu is  . If the values of  and  at the instant of fault clearing are  and 3.762 radian/s respectively, then  (in pu) is _________.