Chapter No.3
Current Electricity MCQ
9th Class
Maharashtra State Board
Multiple Choice Questions
1 |
The
S.I unit of power is? |
A |
Henry
|
B |
Coulomb |
C |
Watt |
D |
Watt-hour |
ANS |
Watt |
2 |
Electric
pressure is also called? |
A |
Resistance |
B |
Power
|
C |
Voltage
|
D |
Energy |
ANS |
Voltage |
3 |
Out
of the following which is not a poor conductor? |
A |
Cast
iron |
B |
Copper
|
C |
Carbon |
D |
Tungsten |
ANS |
Copper |
4 |
The
substances which have a large number of free electrons and offer a low
resistance are called? |
A |
Insulators |
B |
Inductors |
C |
Semi-conductors |
D |
Conductors |
ANS |
Conductors |
5 |
Out
of the following which is an insulating material? |
A |
Copper
|
B |
Gold
|
C |
Sliver |
D |
Paper |
ANS |
Paper |
6 |
Conductance
is reciprocal of? |
A |
Resistance
|
B |
Inductance |
C |
Reluctance |
D |
Capacitance |
ANS |
Resistance |
7 |
The
property of a conductor due to which it passes current is called? |
A |
Resistance |
B |
Reluctance |
C |
Conductance |
D |
Inductance |
ANS |
Conductance |
8 |
The
resistance of a conductor varies inversely as? |
A |
Length |
B |
Area
of cross-section |
C |
Temperature |
D |
Resistivity |
ANS |
Area
of cross-section |
9 |
With
rise in temperature the resistance of pure metal? |
A |
Increases |
B |
Decreases |
C |
First
increases and then decreases |
D |
Remains
constant |
ANS |
Increases |
10 |
With
rise in temperature the resistance of semi-conductors? |
A |
Decreases |
B |
Increases |
C |
First
increases and then decreases |
D |
Remains
constant |
ANS |
Decreases |
11 |
Three
resistances of 10 ohms, 15 ohms and 30 ohms are connected in parallel. The
total resistance of the combination is? |
A |
50
ohms |
B |
10
ohms |
C |
15
ohms |
D |
55
ohms |
ANS |
50
ohms |
12 |
An
instrument which detects electric current is known as? |
A |
Voltmeter |
B |
Rheostat |
C |
Wattmeter |
D |
Galvanometer |
ANS |
Galvanometer |
13 |
In
a circuit a 33Q resistor carries a current of 2A. The voltage a cross the
resistor is? |
A |
33
V |
B |
66
V |
C |
80
V |
D |
132
V |
ANS |
66
V |
14 |
A
light bulb draws 300 mA when the voltage across it is 240 V. The resistance
of the light bulb is? |
A |
400
Q |
B |
600
Q |
C |
800
Q |
D |
1000
Q |
ANS |
800
Q |
15 |
The
resistance of a parallel circuit consisting of two branches is 120 ohms. It
the resistance of one branch is 18 ohms, what is the resistance of the
others? |
A |
18
Q |
B |
36
Q |
C |
48
Q |
D |
64
Q |
ANS |
36
Q |
16 |
Which
of the following material has nearly zero temperature co-efficient of
resistance? |
A |
Magnanin
|
B |
Porcelain
|
C |
Carbon |
D |
Copper |
ANS |
Magnanin |
17 |
You
have to replace 1500 Q resistor in ratio. You have no 1500 Q resistor but
have several 1000 Q ones which you would connect? |
A |
Two
in parallel |
B |
Two
in parallel and one in series |
C |
Three
in parallel |
D |
Three
in series |
ANS |
Two
in parallel and one in series |
18 |
Two
resistors are said to be connected in series when? |
A |
Same
current passes in turn through both |
B |
Both
carry the same value of current |
C |
Total
current equals the sum of branch currents |
D |
Sum
of IR drops equals the applied e.m.f |
ANS |
Same
current passes in turn through both |
19 |
Which
of the following statement is true both for a parallel D.C circuit? |
A |
Elements
have individual currents |
B |
Currents
are additive |
C |
Voltages
are additive |
D |
Power
are additive |
ANS |
Power
are additive |
20 |
Which
of the following materials has a negative temperature co-efficient of resistance? |
A |
Copper
|
B |
Aluminum |
C |
Carbon |
D |
Brass |
ANS |
Carbon |
21 |
Ohm’s
law is not applicable to? |
A |
Vacuum
tubes |
B |
Carbon
resistors |
C |
High
voltage circuits |
D |
Circuits
with low current densities |
ANS |
Vacuum
tubes |
22 |
For
which of the following ‘ampere second’ could be the unit? |
A |
Reluctance
|
B |
Charge |
C |
Power
|
D |
Energy |
ANS |
Charge |
23 |
Which
is the best conductor of electricity? |
A |
Iron
|
B |
Silver |
C |
Copper |
D |
Carbon |
ANS |
Silver |
24 |
Which
one of the following does not have negative temperature co-efficient? |
A |
Aluminum |
B |
Paper |
C |
Rubber
|
D |
Mica |
ANS |
Aluminum
|
25 |
Varistors
are? |
A |
Insulators |
B |
Non-linear
resistor |
C |
Carbon
resistors |
D |
Resistors
with zero temperature |
ANS |
Non-linear
resistor |
26 |
The
rating of a fuse wire is always expressed in? |
A |
Ampere
– hours |
B |
Ampere
– volts |
C |
Kwh |
D |
Amperes |
ANS |
Amperes |
27 |
The
filament of an electric bulb is made of? |
A |
Carbon |
B |
Aluminum |
C |
Tungsten |
D |
Nickel |
ANS |
Tungsten |
28 |
A
3 Q resistor having 2 A current will dissipate the power of? |
A |
2
watts |
B |
4
watts |
C |
6
watts |
D |
8
watts |
ANS |
6
watts |
29 |
The
resistance of a few meters of wire conductor in closed electrical circuit is? |
A |
Practically
zero |
B |
Low
|
C |
High |
D |
Very
heigh |
ANS |
Practically
zero |
30 |
A caused
switch has a resistance of? |
A |
Zero |
B |
About
50 ohms |
C |
About
500 ohms |
D |
Infinity |
ANS |
Zero |
31 |
The
hot resistance of the bulb’s filament is higher than its could resistance
because the temperature co-efficient of the filament is? |
A |
Zero |
B |
Negative |
C |
Positive |
D |
About
2 ohms per degree |
ANS |
Positive |
32 |
The
thickness of insulation provided on the conductor depends on? |
A |
The
magnitude of voltage on the conductor |
B |
The
magnitude of current flowing through it |
C |
Both
A and B |
D |
None
of the above |
ANS |
The
magnitude of voltage on the conductor |
33 |
Which
of the following quantities remain the same in all parts of a series circuit? |
A |
Voltage |
B |
Current |
C |
Power |
D |
Resistance |
ANS |
Current |
34 |
A
40w bulb is connected in series with a room heater. If now 40 w bulb is
replaced by 100w bulb, the heater output will? |
A |
Decreases
|
B |
Increases |
C |
Remain
same |
D |
Heater
will burn out |
ANS |
Increases |
35 |
An
electric filament bulb can be worked from? |
A |
D.C
supply only |
B |
A.C
supply only |
C |
Battery
supply only |
D |
All
above |
ANS |
All
above |
36 |
Electric
current passing through the circuit produces? |
A |
Magnetic
effect |
B |
Luminous
effect |
C |
Thermal
effect |
D |
Chemical
effect |
ANS |
Thermal
effect |
37 |
If
the efficiency of a machine is to be high, what should be low? |
A |
Input
power |
B |
Losses |
C |
True
component of power |
D |
Kwh
consumed |
ANS |
Losses |
38 |
A
glass rod when rubbed with silk cloth is changed because? |
A |
It
tubes in proton |
B |
Its
atoms are removed |
C |
It
gives away electrons |
D |
It
gives away positive charge |
ANS |
It
gives away electrons |
39 |
Whether
circuit may be AC on DC one, following is most effective in reducing the
magnitude of the current? |
A |
Reactor
|
B |
Capacitor |
C |
Inductor |
D |
Resistor |
ANS |
Resistor |
40 |
When
electric current passes through a bucket full of water, lot of bubbling is
observed. This suggests that the type of supply is? |
A |
A.C |
B |
D.C |
C |
Any
of above two |
D |
None
of the above |
ANS |
D.C |
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