The moving coil in a dynamometer wattmeter is connected

In an oscilloscope the input to the horizontal plates is a $$100Hz$$ voltage signal. The lissajous patterns $$(A), (B)$$ and $$(C)$$ will be generated when different frequency voltage signals are applied to vertical plates. Match each lissajous pattern to the corresponding frequency by

In Figure. The characteristic that corresponds to the variation of synchronous reactance of synchronous motor with field current is

Unbalanced supply voltage given to a $$3-$$ phase, data-connected induction motor will cause