Explore topic-wise MCQs in Testing Subject.

This section includes 657 Mcqs, each offering curated multiple-choice questions to sharpen your Testing Subject knowledge and support exam preparation. Choose a topic below to get started.

1.

In parallel connection the current flows through each resistor is?

A. maximum
B. same
C. None of these
D. different
Answer» E.
2.

When resistors are connected in parallel the reciprocal of the equivalent resistance is equal to?

A. the sum of individual resistances.
B. product of the individual resistances
C. the sum of the reciprocals of the individual resistances
D. None of these
Answer» D. None of these
3.

According to Ohm's law?

A. V = 12R
B. V = IR
C. V = 1R2
D. V = I2R2
Answer» C. V = 1R2
4.

Only for non-metallic resistance.

A. Only for non-metallic resistance.
B. None of these.
C. only for metallic resistance at a given temperature and for steady currents
D. only for steady currents.
Answer» D. only for steady currents.
5.

The terminal potential difference of a battery becomes equal to its e.m.f when its internal resistance, is?

A. maximum
B. very low
C. infinite
D. zero
Answer» E.
6.

A dry cell supplies?

A. None of above
B. Both alternating and direct current
C. direct current
D. alternating current
Answer» D. alternating current
7.

The unit of resistivity is?

A. Ohm
B. Ohm—m3
C. Ohm-m2
D. Ohm—m
Answer» E.
8.

When a temperature rises, the drift velocity of the free electrons decreases. Hence for given applied voltage?

A. the electric current decreases, which increases the electrical resistance
B. the electric current decreases, which increases the electrical resistance
C. None of the above.
D. only electric resistance decrease and current remain same
Answer» B. the electric current decreases, which increases the electrical resistance
9.

Metal resistors that conduct in accordance with Ohm's law are said to be?

A. Ohms component
B. Ohmic
C. Ohmmeter
D. Omega
Answer» C. Ohmmeter
10.

In parallel connection, the potential different across each resistors is?

A. zero
B. same
C. different
D. maximum
Answer» C. different
11.

The internal resistance of a cell of emf 12 V is 5 x 10 -2 Ω . It is connected across an unknown resistance. Voltage across the cell, when a current of 60 A is drawn from it, is

A. 15 V
B. 12 V
C. 6 V
D. 15 V
Answer» E.
12.

The resistance of an incandescent lamp is

A. Greater when switched off
B. The same whether it is switched off or switched on
C. Smaller when switched on
D. None of these
Answer» D. None of these
13.

Read the following statements carefully Y: The resistivity of a semiconductor decreases with increase of temperature Z : In a conducting solid, rate of collisions between free electrons and ions increases with increases of temperature Select the correct statements (s) from the following

A. Both Y and Z are true
B. Y is false but Z is true
C. Y is true and Z is the correct reason for Y
D. Y is true but Z is false
Answer» B. Y is false but Z is true
14.

A uniform wire of resistance R is uniformly compressed along its length, until its radius becomes n times the original radius. New resistance of the wire becomes

A. nR
B. R/n2
C. R/n4
D. R/n
Answer» D. R/n
15.

A uniform resistance wire of length L and diameter d has a resistance R. Another wire of same material has length 4L and diameter 2d, the resistance will be

A. R/2
B. 2R
C. R
D. R/4
Answer» D. R/4
16.

Identify the set in which all the three materials are good conductor of electricity

A. Cu, Ag, Au
B. Cu, Ag, Au
C. Cu, Si, Diamond
D. Cu, Ge, Hg
Answer» B. Cu, Ag, Au
17.

Two resistance r1 and r2 (r1 < r2 ) are connected in parallel. Their equivalent resistance R is

A. r1 < R < ( r1 + r2)
B. R < r1
C. r1 < R < r2
D. R < ( r1 > r2)
Answer» C. r1 < R < r2
18.

Three resistors are connected to form the sides of a triangle ABC, the resistance of the sides AB, BC and CA are 40 ohms; 60 ohms and 100 ohms respectively. The effective resistance between the points A and B in ohms will be

A. 64
B. 200
C. 50
D. 32
Answer» E.
19.

A wire of 50 cm long and 1 mm2 in cross-sectional area carries a current 4A when connected to a 2V battery. The resistivity of the wire is

A. 4 x 10-6 Ωm
B. 2 x 10-7 Ωm
C. 5 x 10-7 Ωm
D. 1 x 10-6 Ωm
Answer» E.
20.

Which of the following does not obey Ohm's law

A. Diode-valve
B. Copper
C. Aluminium
D. None of these
Answer» B. Copper
21.

Resistance of a wire is r ohms. The wire is stretched to double its length, then its resistance in ohms is

A. 4 r
B. 2 r
C. r / 2
D. r / 4.
Answer» B. 2 r
22.

Two bulbs marked 200 watt-250 volts and 100 watt-250 volts are joined in series to 250 volts supply. Power consumed in circuit is

A. 33 watt
B. 100 watt
C. 67 watt
D. 300 watt.
Answer» D. 300 watt.
23.

Superposition theorem is not applicable for

A. voltage calculation
B. bilateral elements
C. passive elements
D. power calculations
Answer» E.
24.

The charge on an electron is known to be 1.6 x 10-19 coulomb. In a circuit the current flowing is 1 A. How many electrons will be flowing through the circuit in a second?

A. 0.625 x 1019
B. 1.6 x 10-19
C. 1.6 x 1019
D. 0.625 x 1012.
Answer» B. 1.6 x 10-19
25.

Which of the following theorem is applicable for both linear and non-linear circuits ?

A. None of these
B. Norton theorem
C. Superposition theorem
D. Thevenin theorem
Answer» B. Norton theorem
26.

The value of the following is given by 100 (kilo ampere ) x ( micro ampere ) 100 milli ampere * 10 ampere

A. 0.001 A
B. 0.1 A
C. 10A.
D. 0.041666667
Answer» C. 10A.
27.

A cell of internal resistance 3 ohm and emf 1 volt is connected to a uniform wire of length 500 em and resistance 3 ohm. The potential gradient in the wire is

A. 30 mV/cm
B. 1 mV/cm
C. 4 mV/cm
D. 20 mV/cm
Answer» C. 4 mV/cm
28.

The resistance of a coil is 4.2 Ω at 100°C and the temperature coefficient of resistance of its material is 0.004 °C. Its resistance at Q °C is

A.
B. 6.5 C
C.
D.
Answer» D. 4Ω
29.

A circuit contains two un-equal resistances in parallel

A. potential difference across each is same
B. smaller resistance has smaller conductance.
C. large current flows in larger resistor
D. current is same in both
Answer» B. smaller resistance has smaller conductance.
30.

The resistors of resistances 2 Ω, 4 Ω and 8 Ω are connected in parallel, then the equivalent resistance of the combination will be

A. 7/4 Ω
B. 8/7 Ω
C. 7/8 Ω
D. 4/9 Ω
Answer» C. 7/8 Ω