Current electricity

11. The condition for the validity under Ohm’s law is that

Resistance must be uniform
Current should be proportional to the size of the resistance
Resistance must be wire wound type
Temperature at positive end should be more than the temperature at negative end

Detailed SolutionThe condition for the validity under Ohm’s law is that

12. When electric current passes through a bucket full of water, lot of bubbling is observed. This suggests that the type of supply is

A.C.
D.
B.
None of the above

Detailed SolutionWhen electric current passes through a bucket full of water, lot of bubbling is observed. This suggests that the type of supply is

13. Resistance of carbon filament lamp as the applied voltage increases.

Increases
Decreases
Remains same
None of the above

Detailed SolutionResistance of carbon filament lamp as the applied voltage increases.

14. Voltage dependent resistors are usually made from

Charcoal
Silicon carbide
Nichrome
Graphite

Detailed SolutionVoltage dependent resistors are usually made from

15. Which is the best conductor of electricity?

Iron
Silver
Copper
Carbon

Detailed SolutionWhich is the best conductor of electricity?

16. The resistance of a parallel circuit consisting of two branches is 12 ohms. If the resistance of one branch is 18 ohms, what is the resistance of the other?

18 ohms
36 ohms
48 ohms
64 ohms

Detailed SolutionThe resistance of a parallel circuit consisting of two branches is 12 ohms. If the resistance of one branch is 18 ohms, what is the resistance of the other?

17. Conductance: mho ::

Resistance : ohm
Capacitance : Henry
Inductance : farad
lumen : steradian

Detailed SolutionConductance: mho ::

18. When a voltage of one volt is applied, a circuit allows one micro ampere current to flow through it. The conductance of the circuit is

1 n-mho
106 mho
1 milli-mho
None of the above

Detailed SolutionWhen a voltage of one volt is applied, a circuit allows one micro ampere current to flow through it. The conductance of the circuit is

19. Which of the following material has nearly zero temperature coefficient of resistance?

Manganin
Porcelain
Carbon
Copper

Detailed SolutionWhich of the following material has nearly zero temperature coefficient of resistance?

20. The hot resistance of the bulb’s filament is higher than its cold resistance because the temperature coefficient of the filament is

Zero
Negative
Positive
About 2 ohms per degree

Detailed SolutionThe hot resistance of the bulb’s filament is higher than its cold resistance because the temperature coefficient of the filament is

Page 1Page 2Page 3Page 4Page 5
Test 1Test 2