232. If one line conductor of a 3-phase line is cut, the load is then supplied by voltage.
A. single phase
B. two phae
C. three phase
D. none of the above
233. The power factor of the load shown in is star-connected
A. 60?
B. 30?
C. 120?
D. none of the above
234. In the circuit shown in Fig. 5.26, the phase sequence is RYB. If the load p.f. is cos q) lagging, then reading of wattmeter W2 will be
A. VL1L cos (30? ? (1))
B. VL1L cos (30? + q))
C.VL1L sin (30? +
D.VOL cos (30? +
235. In two wattmeter method, the algebraic sum of the readings of two wattmeters will indicate true power only if
A. the load is balanced
B. phase sequence remains unchanged
C. there is no source unbalance
D. neutral wire available does not carry any current
236. The most difficult unbalanced 3-phase load to deal with is
A. 4-wire star connected unbalanced load
B. unbalanced A-connected load
C. unbalanced 3-wire, Y-connected load
D. lnone of the above
237. In a three-phase circuit, the total instantaneous power is equal to instantanelous power per phase multiplied by
A.3
B.6
C.2.5
D.1.5
238. In the two-wattmeter method 013-phase power measurement, the load is resistive. The readings of the wattmeters are WI and W2. Then,
A. W1 may be greater than W2
B. WI may be less the W2
C. W1 = W2
D. none of the above
Page 34 of 36