Basic Electrical Engineering: Part-12

Basic Electrical Engineering Objective Questions

[1] Power is defined as

a) The rate at which current flows in a circuit

b) The product of voltage and resistance in a circuit

c) The rate at which energy is radiated or dissipated

d) The accumulation of energy over time

e) The amount of heat generated in a circuit.

Ans:C

[2] At the exact moment a 60Hz ac sine wave is at its positive peak voltage, the instantaneous rate of change in the voltage is

a) Large and positive

b) Small and negative

c) Large and negative

d) Small and negative

e) Zero

Ans: E

[3] A flute sounds different than a violin, even if the two instruments are played at the same pitch, because of a difference in the

a) Phase

b) Chamber length

c)  Frequency

d) Waveform

e)  Bias

Ans:D

[4] A common-collector transistor circuit is often used

a)  To provide high gain and sensitivity over a wide range of frequencies

b)  To match a high impedance to a low impedance

c)  As a high-fidelity audio power amplifier

d)  As an oscillator at microwaves frequencies

e)  As the rectifier in a dc power supply.

Ans: B

[5] The internal conductance of an ammeter is generally

a)  Low

b)  Directly proportional to the current

c)  Inversely proportional to the current

d)  High

e)  Any value. It doest matter

Ans: D

[6] A steady magnetic field can be produced by

a)  A straight wire carrying a constant direct current.

b)  A loop of wire carrying a constant direct current.

c)  A coil of wire carrying a constant direct current.

d)  A constant-intensity stream of protons in free space, moving in a straight line.

e)  Any of the above.

Ans:E

[7] The output wave of a common-gate amplifier circuit with a pure sine-wave input

a)  Is in phase with the input wave.

b)  Lags the input wave by 90° of phase.

c)  Leads the input wave by 90° of phase.

d)  Is 180° out of phase with the input wave.

e)  Is inverted with respect to the input wave.

Ans:A

[8] Which of the following capacitor types is polarized?

a)  Electrolytic

b)  Paper

c)  Ceramic

d)  Mica

e)  Air variable

Ans: A

[9] when a non zero net reactance exists in an ac circuit, the apparent power is

a)  Zero

b)  Equal to the true power

c)  Less than the true power

d)  Greater than the true power

e)  Infinite

Ans: D

[10] The gauss is a unit of

(a) Charge carrier flow speed.

(b) Magnetic flux density.

(c) Electrostatic field strength.

(d) Electromagnetic field intensity.

(e) Electrical charge quantity.

Ans:B. Exp: In SI system the unit is tesla(T). In CGS system the unit is Gauss

[11] An average responding rectifier type electronic ac voltmeter has its scale calibrated in terms of the rms value of a sine wave, when a square wave voltage of peak magnitude 100V is measured using this voltmeter then the reading indicated by the meter, will be ?
a) 111V
b) 100V
c) 90.09V
d) 70.7V

Ans:B

[12] A house served by a 220V supply light, is protected by a 9-Ampere fuse. The maximum number of 60 W bulbs in parallel that can be turned on is
a) 11
b) 33
c) 22
d) 44

Ans: B

[13] Silicon has a preference in IC technology because
(a) It is an indirect semiconductor
(b) It is a covalent semiconductor
(c) It is an elemental semiconductor
(d) Of the availability of nature oxide SiO

Ans:D

[14] Three equal resistance of magnitude 5 Ohm each are connected in delta. The resistance between any two pair of terminals of the delta will be
(a) 5 Ohm 
(b) 5/3 Ohm
(c) 10/3 Ohm 
(d) 3/5 Ohm

Ans: C

[15] The R.M.S. value of a half wave rectified sinusoidal alternating current with peak value Im is
(a) Im / 1 

(b) Im / v2

(c) Im / 2 
(d) Im v3
Answer: c)

Ans: C