Question and Answer related to current | Electrical Questions

Question and Answer related to current | Electrical Questions

Question and Answer related to current | Electrical Questions


There will be more useful questions and answers of current which will be mentioned below, All questions are very helpful to all electrical engineer!!


Question and Answer related to current | Electrical Questions


Question and Answer


Q.1. The flow of current in solids is due to

(a) electrons

(b) electrons and ions

(c) atoms

(d) nucleus

Ans.

 (a) electrons
Q.2. The resistance of human body is
around

(a) 5 ohms

(b) 25 ohms

(c) 250 ohms 

(d) 1000 ohms

Ans.

 (d) 1000 ohms
Q.3. The draft velocity of electrons is

(a) very small as compared to speed of
light

(b) equal to speed of light

(c) almost equal to speed of light

(d) greater than speed of light

Ans.
(a) very small as compared to speed of
light
Q.4. One commercial unit of energy equals

(a) 500 watt-seconds

(b) One watt-hour

(c) One kilowatt-hour

(d) ten kilowatt-hour

Ans.

 (c) One kilowatt-hour
Q.5. One coulomb charge equals the charge
on

(a) 6.24 x 1012 electrons

(b) 6.24 x 1014 electrons

(c) 6.24 x 1016 electrons

(d) 6.24 x 1018 electrons

Ans.

 (d) 6.24 x 1018 electrons
Q.6. The electrical energy required to heat
a bucket of water to a certain
temperature is 4 kWh. If the heat losses
are 20 percent, the energy input is

(a) 2 kWh

(6) 3.2 kWh

(c) 5 kWh

(d) 6 kWh

Ans.

 (c) 5 kWh
Q.7. In gases the flow of current is due to

(a) electrons only

(6) positive ions only

(c) electrons and positive ions

(d) electrons, positive ions and nega-
tive ions

Ans.
(d) electrons, positive ions and nega-
tive ions
Q.8. The maximum current rating for a 10
ks2, 0.5 W resistor is

(a) 0.707 mA

(b) 7.07 mA

(c) 14.14 mA 

(d) 28.28 mA

Ans.

 (b) 7.07 mA
Q.9. An electrical lamp consumes 100 W of
power. If the supply voltage is 220V the
energy consumed in 30 minutes is

(a) 0.005 kWh

(b) 0:05 kWh

(c) 0.5 kWh

(d) 5 kWh

Ans.

 (b) 0:05 kWh
Q.10. The S.I. unit of power is

(a) henry

(b) coulomb

(c) watt

(d) watt-hour

Ans.

 (c) watt
Q.11. Electric pressure is also called

(a) resistance

(b) power

(c) voltage

(d) energy

Ans.

 (c) voltage
Q.12. 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.

 (d) conductors
Q.13. Out of the following which is not a poor
conductor ?

(a) Cast iron

(b) Copper

(c) Carbon

(d) Tungsten

Ans.

 (b) Copper
Q.14. Out of the following which is an
insulating material ?

(a) Copper

(b) Gold

(c) Silver

(d) Paper

Ans.

 (d) Paper
Q.15. The property of a conductor due to
which it passes current is called

(a) resistance

(b) reluctance

(c) conductance

(d) inductance

Ans.

 (c) conductance
Q.16. Conductance is reciprocal of

(a) resistance

(b) inductance

(c) reluctance

(d) capacitance

Ans.

(a) resistance


Q.17. The resistance of a conductor varies
inversely as

(a) length

(b) area of cross-section

(c) temperature

(d) resistivity

Ans.

 (b) area of cross-section
Q.18. With rise in temperature the resistance
of pure metals

(a) increases

(b) decreases

(c) first increases and then decreases

(d) remains constant

Ans.

 (a) increases
Q.19. With rise in temperature the resistance
of semi-conductors

(a) decreases

(b) increases

(c) first increases and then decreases

(d) remains constant

Ans.

 (a) decreases
Q.20. The resistance of a copper wire 200 m
long is 21 12. If its thickness (diameter)
is 0.44 mm, its specific resistance is
around

(a) 1.2 x 10-6 2-m

(b) 1.4 x 10- Q-m

(c) 1.6 x 10-22-m

(d) 1.8 x 10-22-m