Q.4:
Which of the following can have negative temperature coefficient _____________?O
A.
Compounds of silver
B.
Liquid metals
C.
Metallic alloys
D.Electrolytes
Q.5:
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___________?
A.1 n-mho
B.
106 mho
C.
1 milli-mho
D.
none of the above
Q.6:
Nichrome wire is an alloy of_____________?*
A.
lead and zinc
B.
chromium and vanadium
C.nickel and chromium
D.
copper and silver
Q.7:
If/, R and t are the current, resistance and time respectively, then according to Joules law heat produced will be proportional to_______________?
A.I2Rt
B.
I2Rf
C.
I2R2t
D.
I2R2t*
Q.8:
A thermistor has_____________?
A.
positive temperature coefficient
B.
negative temperature coefficient
C.zero temperature coefficient
D.
variable temperature coefficient
Q.9:
With three resistances connected in parallel, if each dissipates 20 W the total power supplied by the voltage source equals_____________?
A.
10 W
B.
20 W
C.
40 W
D.60 W
Q.10:
The number of electrons in the outer most orbit of carbon atom is___________?M