20. The magnitude of three phase fault currents at buses A and B of a power system are $$10pu and 8pu$$, respectively. Neglect all resistances in the system and consider the pre-fault system to be unloaded. The pre-fault voltage at all buses in the system is $$1.0pu$$. The voltage magnitude at bus B during a three phase fault at bus $$A is 0.8pu$$. The voltage magnitude at bus A during a three phase at bus B, in pu, is _________?
Voltage at bus B after 3 phase fault at $$A = 0.8pu$$