An electric motor with 'constant output power' will have a torque speed characteristic in the form of a

A single-phase transformer is to be switched to the supply to have minimum inrush current. The switch should be closed at

The core flux of a practical transformer with a resistive load

A 3-phase transformer has rating of 20 MVA, 220 kV (star) / 33 kV (delta) with leakage reactance of 12%. The transformer reactance (in ohms) referred to each phase of the L.V. delta-connected side is