288. Voltage of a particular bus can be controlled by controlling the

A. phase angle.

B. reactive power of the bus

C. active power of the bus. phase angle andreactive power.

D.

289. If 8 is the loss angle of the cable, its power factor is

A. sin 5

B. cos

C. is independent of 5

D. none of these

290. Reactance relay is normally preferred for protection against

A. earth faults only.

B. phase faults only.

C. both (a) and (b) above

D. none of the above.

291. Inertia constant H of a machine of 200 MVA is 2 p.u. its value corresponding to 400 MVA will be

A.4

B.2

C.4

D.0.5

292. Inertia constant of two groups of machines, which swing together are M4 and M2. The inertia constant of the system is

A. M4 M2

B. M4 ? M2

C.M4M2

D. none of the above

293. Inertia constant of two groups of machines which do not swing together are M4 and M2 such that M4> M2. It is proposed to add some inertia to one of the two groups of machines for improving the transient stability of the system. It should be added to

A. M4

B. M2

C. It does not matter whether to add to M4 or M2

D. none of the above

294. For load flow solution the quantities specified at a load bus are

A. P and Q

B. P and I V I

C. Q and I V I

D. P and 8

Page **42** of **54**