Complex AC MCQs

Question 1

In a practical parallel resonant circuit

Accepted Answer

IL > Ic

Answer

IL = lc

Answer

IL < lc

Answer

IL = 100 lc

Question 2

In a parallel resonant LC circuit, the line current is

Accepted Answer

much less than IL or lc

Answer

equal to IL or lc

Answer

much greater than IL or lc

Answer

none of above

Question 3

Pure inductive circuit

Accepted Answer

takes power from the line during some part of the cycle and then returnsback to it during other part of the cycle

Answer

consumes some power onaverage

Answer

(d) does not take power at all from a line

Answer

none of the above

Question 4

Inductance affects the direct current flow

Accepted Answer

at the time of turning on and off

Answer

only at the timeof turning off

Answer

only at the time of turning on

Answer

at all the time of operation

Question 5

Inductance of a coil varies

Accepted Answer

All the above

Answer

directly as the cross-sectional area of magnetic core

Answer

directly as square of number of turns

Answer

directly as the permeability of the core

Question 6

Time constant of an inductive circuit

Accepted Answer

increases with increase of inductance and decrease of resistance

Answer

increases with the increase of inductance and the increase of resistance

Answer

increases with decrease of inductance and decrease of resistance

Answer

increases with decrease of inductance and increase of resistance

Question 7

Power factor of an inductive circuit is usually improved by connecting capacitor to it in

Accepted Answer

parallel

Answer

series

Answer

either (a) or (b)

Answer

ncne of the above

Question 8

Power factor of the systemis kept high

Accepted Answer

due to all above reasons

Answer

to reduce line losses

Answer

to maximise the utilization of the capacities of generators, lines and transformers

Answer

to reduce voltage regulation of the line

Question 9

The time constant of the capacitance circuit is defined as the time during which voltage

Accepted Answer

rise to 63.2% of its final steady value

Answer

falls to 36.8% of its final steady value

Answer

rises to 38.6% of its final steady value

Answer

none of the above