A three-phase, $11$ kV, $50$ Hz, $2$ pole, star connected, cylindrical rotor synchronous motor is connected to an $11$ kV, $50$ Hz source. Its synchronous reactance is $50 \Omega$ per phase, and its stator resistance is negligible. The motor has a constant field excitation. At a particular load torque, its stator current is $100$ A at unity power factor. If the load torque is increased so that the stator current is $120$ A, then the load angle (in degrees) at this load is __________.