A certain application requires power at a frequency of 16.67 Hz , while the available grid frequency is 50 Hz . A 3-phase synchronous motor connected to the $50 \mathrm{~Hz}, 3$-phase grid, driving a synchronous generator, is used for this application.

Which one of the following combinations is a suitable choice for the number of poles in the motor and generator, respectively?

The figure shows the single-line diagram of a synchronous generator delivering $\mathrm{P}=50 \mathrm{MW}$ of power at unity power factor to an infinite bus.

$I_s$ denotes the stator current phasor. If the field excitation is increased, which one of the following options correctly describes its effect on the stator current, power factor, and load angle of the machine?

Instruments required to synchronize an alternator to the grid is/are

The induced emf in a 3.3 kV , 4-pole, 3-phase, star-connected synchronous motor is considered to be equal and in phase with the terminal voltage under no load condition. On application of a mechanical load, the induced emf phasor is deflected by an angle of $2^{\circ}$ mechanical with respect to the terminal voltage phasor. If the synchronous reactance is $2 \Omega$, and stator resistance is negligible, then the motor armature current magnitude, in ampere, during loaded condition, is closest to __________ . (round off to two decimal places)