197. The power factor of a series R-L-C circuit at its half-power points is

A. unity

B. lagging

C. leading

D. lagging or leading

198. The voltage applied across an R-L circuit is equal to

A. phasor sum

B. arithmetic sum

C. sum of the squares

D. algebraic sum

199. A parallel A.C. circuit in resonance will

A. have current in each section equal to the line current

B. have a high voltage developed across each inductive and capacitive section

C. act like a resistor of low value

D. have a high impedance

200. The dynamic impdeance of an R-L and C parallel circuit at resonance is ohm

A. R/LC

B. C/LR

C. LC/R

D. L/CR

201. A parallel resonant circuit can be used

A. as a high impedance

B. to reject a small band of frequencies

C. both (a) and (b)

D. to amplify certain frequencies

202. In a power system, reactive power is necessary for

A. power transmission

B. stabilishing the voltage level

C. counteracting the effect of reactance in the transmission system

D. none of the above

203. The ratio of the bandwidth to the resonance frequency is called the

A. impedance

B. susceptance

C. quality factor

D. selectivity

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