Important Question Electrical Engineer

The current through an inductance follows :

(1) A linear growth

(2) A linear decay

(3) An exponential decay

(4) An exponential growth

Ans (4)

Selectivity's of different resonance circuits are compared in terms of their :

(1) Impedances

(2) Reactance

(3) Frequencies

(4) Band widths

Ans (4)

The dynamic impedance of an R-L and C parallel circuit at resonance is

(1) R/LC

(2) C/LR

(3) LC/R

(4) L/CR

Ans (4)

1. Inductive reactance is defined as the opposition offered by the........ of a circuit to the flow of an alternating sinusoidal current.

(1)Resistance

(2) Inductance

(3)Capacitance

(4) Voltage

Ans (2)

1. A power system is providing 250V A.C at 20 A. If the phase angle between current and voltage is 25° than what is the truelongest power used by the system.

(1) 2113.8 W

(2) 4531.5 W

(3) 5517.2W

(4) 11831.6 W

Ans (2)

To calculate the power factor which of the following is odd one :

(1) True power

(2) P/VI

(3) R/Z

(4) V/I

Ans (4)

Unit of reactive power is :

(1) Watt

(2) Kiol watt

(3) VAR

(4) Volt ampere

Ans (3)

When X L is equal to X C :

(1) Z = R

(2) Z = X C

(3) Z = X L

(4) None of these

Ans (1)

At resonance , inductive reactance is equal :

(1) Resistance

(2) Capacitance

(3) Capacitive Reactance

(4) Inductance

Ans (3)

1. Three identical impedance are connected in delta to 3 phase supply of 400 V. The line current is 34.65 A and the total power taken is 14.4 kW. What is the resistance of the load in each phase ?

(1) 20

(2) 16

(3) 12

(4) 10

Ans (3)