GATE 2019: Power System Test 9 (App update required to attempt this test)

Consider the following figure shown below.

It shows electric power input P_e to a lossless synchronous motor as a function of torque angle The load is suddenly increased from Po to Ps and the motor oscillates around _sbetween _oand _m^.
Consider the following statements derived from the figure regarding the relationship between the motor speed ω and its synchronous speed ω_s at different point in the oscillating cycle.
A) At point 1, ω= ω_s
B) At point 2, while oscillating from 1 towards 3, ω<ω_s
C) At point 3, ω>ω_s
D) At point 2, while oscillating from 3 towards 1, ω>ω_s
Which of the above statements is/are correct?

The synchronous generator is delivering 1.0 pu of power to an infinite bus. Infinite bus voltage is 1.1 pu. Generator is connected to infinite bus through a lossless transmission line. A circuit breaker is connected near to generator terminal and the critical clearing time of circuit breaker is 0.34 sec. if another identical synchronous generator is connected in parallel to the exciting generator and each generator is scheduled to supply 0.5 per unit of power, then the critical clearing time (in sec) of the circuit breaker will –

A 500 MW, 21 k V, 50 Hz , 3 – phase 2 pole synchronous generator having unity power factor has a moment of inertia of 20× 10³ kg – m². calculate inertia constant in MJ/MVA –

A relay at rating 8 A, 2.2 sec IDMT and having a relay setting of 130% TMS = 0.6. It is connected to a supply circuit through a CT ratio 400/5 ratio. If the fault current is 5000 A, the plug setting multiplier of the relay is

What is the percentage (%) of the alternator winding is protected if The neutral of 10 MVA, 11 kV alternator is earthed through a resistance of 5 ohms. The fault ready is set to operate at 0.75 A. The current transformers have a ratio of 1000/5 is given?