120. Which of the following refers to a parallel circuit?

A. The current through each element is Same

B. The voltage across element is in proportion to its resistance value

C. The equivalent resistance is greater than any one of the resistors

D. The current through any one element is less than the source current

121. A phasor is

A. a line which represents the magnitude and phase of an alternating quantity

B. a line representing the magnitude and directionof an alternating quantity

C. a coloured tag or band for distinction between different phases of a 3-phase supply

D. an instrument used for measuring phases of an unblanced 3-phase load

122. A parallel 4C circuit in resonance will

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

B. have a high impedance

C. act like a resistor of low value

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

123. Wire-wound resistors are unsuitable for use at high frequencies because they

A. create more electrical noise

B. are likely to melt under excessive eddy current heat

C. consume more power

D. exhibit unwanted inductive and capacitive effects

124. The inductance of a coil can be increased bY

A. increasing core length

B. decreasing the number of turns

C. decreasing the diameter of the former

D. choosing core material having high relative permeability

125. The power taken by a 3-, load is given by the expression

A. /3- VLIL sin (1)

B. VOL cos

C. 3 VL1L sin

D. 3 VL1L cos (1)

126. The least number of 1-4) wattmeters required to measure total power consumed by an unbalanced load fed from a 3-(1), 4-wire system is

A. I

B.2

C.3

D.4

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