1. Which
of the following material is not used as fuse material?
(B)
ohm / oC
(A)
Silver
(B)
Copper
(C)
Aluminium
(D)
Carbon
Answer
-(D) Carbon
2. Resistivity
is usually expressed in terms of
(A)
mho
(B)
ohm / oC
(C)
ohms/cm-square
(D)
ohms/cm-cube
3. According
to the fuse law, the current carrying capacity varies as
(A)
diameter
(B)
(diameter)3/2
(C)
1 / diameter
(D)1
/ (diameter)2
Answer
-(B) (diameter)3/2
4. Which of
the following bulbs will have the least resistance ?
(A)
220 V, 60 W
(B)
220 V, 100 W
(C)
115 V, 60 W
(D)
115 V, 100 W.
Answer-(D)
115 V, 100 W
5. Four
identical resistors are first connected in parallel and then in series. The
resultant resistance of the first combination to the second will be
(A)
1 / 16 times
(B)
1 / 4 times
(C)
4 times
(D)
16 times.
Answer-(A)
1 / 16 times
6. When
P = Power, V = Voltage, I = Current, R = Resistance and G = Conductance, which
of the following relation is incorrect?
(A)
V = √ (PR)
(B).
P= V2G
(C)
G= P / I2
(D)
I =√ (P / R)
Answer-(C)
G= P / I2
7. The
unit of electrical conductivity is
(A)
mho / metre
(B)
mho / sq. m
(C)
ohm / metre
(D)
ohm / sq. m.
Answer-(A)
mho / metre
8.
Low resistance can be accurately measured by
(A)
Kelvin bridge
(B
)Wheat stone bridge
(C)
Wein's bridge
(D)
None of the above.
Answer-(A)
Kelvin bridge
9. Resistivity
is usually expressed in terms of
(A)
mho
(B)
ohm / oC
(C)
ohms/cm-square
(D)
ohms/cm-cube.
Answer-(D)
ohms/cm-cube.
10. Which
material is expected to have least resistivity?
(A)
Copper
(B)
Lead
(C)
Mercury
(D)
Zinc.
Answer-(A)
Copper
11.Resistivity of a wire depends on
(A)
length
(B)
material
(C)
cross section area
(D)
none of the above
Answer
-(B) material
12. The
rating of fuse wire is expressed in terms of
(A)
Ohms
(B)
Mhos
(C)
Amperes
(D)
Watts
Answer
-(C) Amperes
13. Three
equal resistors connected in series across a source of emf together dissipate
10 watts of power. What would be the power dissipated in the same resistors
when they are connected in parallel across the same source of emf?
(A) 10 watts
(B) 30 watts
(C) 90 watts
(D) 270 watts.
Answer-(C) 90 watts
14. A heating
element of a hot plate on an electric cooking range draws 12 amperes from 240 V
mains. How many kWh of energy will be consumed in one hour and 15 minutes
(A)
1.2
(B)
3.2
(C)
6.0
(D)
7.2.
Answer-(B)
3.2
15.Low
resistance can be accurately measured by
(A)
Kelvin bridge
(B
)Wheat stone bridge
(C)
Wein's bridge
(D)
None of the above
Answer
-(A) Kelvin bridge
16.A
heating element of a hot plate on an electric cooking range draws 12 amperes
from 240 V mains. How many kWh of energy will be consumed in one hour and 15
minutes
(A)
1.2
(B)
3.2
(C)
6.0
(D)
7.2
Answer
-(B) 3.2
17. Which
resistor will be physically larger in size ?
(A)10
ohm, 50 W
(B)
100 ohm, 10 W
(C)
1 kohm, 1 W
(D)
10 Mohm, 1/ 2 W
Answer
-(A)10 ohm, 50 W
18. Which
material is expected to have least resistivity?
(A)
Copper
(B)
Lead
(C)
Mercury
(D)
Zinc
Answer
-(A) Copper
19. A
fuse is always installed in a circuit is
(A)
Series
(B)
Parallel
(C)
Both A and B
(D)
None of the above
Answer
-(A) Series
20. The
current carrying capacity of the fuse material depends on
(A)
cross-sectional area
(B)
length
(C)
material
(D)
all of the above
Answer
-(D) all of the above
21. Filaments
of electric bulbs are usually made of
(A)
Nichrome
(B)
Tungsten
(C)
Copper
(D)
Carbon
Answer
-(B) Tungsten
22. The
ratio of the resistance of a 100 W, 220 V lamp to that of a 100 W, 110 V lamp
will be nearly
(A)
4
(B)2
(C)
1 / 2
(D)
1 / 4
Answer-(A)
4
23. A
100 W bulb is connected in series with a room heater of 750 W. What will happen
if the bulb is replaced by a 60W bulb?
(A)
Heater output will increase
(B)
Heater output will decrease
(C)
Heater output will remain unchanged
(D)
Bulb will not glow
Answer
-(B) Heater output will decrease
24. For
a fixed supply voltage the current flowing through a conductor will decrease
when
(A)
cross-sectional area of the conductor is increased
(B)
length of the conductor is increased
(C)
length of the conductor is reduced
(D)
cross-sectional area is increased and length is decreased.
Answer
-(B) length of the conductor is increased
25. A
lamp of 100 W at 200 V is supplied current at 100 volts. It will be equivalent
to the lamp of
(A)
50 W
(B)
40 W
(C)
25 W
(D)
10 W
Answer
-(C) 25 W
26. When
current flows through heater coil it glows but supply wiring does not glow
because
(A)
supply wiring is covered with insulation layer
(B)
current through supply line flows at slower speed.
(C)
supply wires arc made of superior material
(D)
resistance of heater coil is more than that supply wires.
Answer
-(D) resistance of heater coil is more than that supply wires
27. Two
electric bulbs of 100 W, 200 V are put in series and the combination is
supplied 100 V. The power consumption of each bulb will be
(A)
100 / 2 W
(B)
100 / 4 W
(C)
100 / 8 W
(D)
100 / 16 W
Answer
-(D) 100 / 16 W
28. Which
of the following lamps will have least resistance at room temperature ?
(A)
200 W, 220 V
(B)
100 W, 220 V
(C)
60 W, 220 V
(D)
25 W, 220 V
Answer
-(A) 200 W, 220 V
29. The
value of supply voltage for 500 W ,5 ohm load is
(A)
500 V
(B)
100V
(C)
50 V
(D)
10V
Answer
-(C) 50 V
30. 100
resistors of 100 ohms each arc connected in parallel. Their equivalent
resistances will be
(A)
10,000 ohms
(B)
100 ohms
(C)
1 ohm
(D)
1/ 10000 ohm
Answer
-(C) 1 ohm
