An electric motor is a device which transforms :
mechanical energy to electrical energy
heat energy to electrical energy
electrical energy to heat energy only
electrical energy to mechanical energy
The north-south polarities of an electromagnet can be found easily by using :
Fleming's right-hand rule
Fleming's left-hand rule
Clock face rule
Left-hand thumb rule
Fuse wire is generally made of alloy of
Tin and lead
Nichrome
Lithium
Copper
The unit of self inductance is
henry
weber/m2
siemens
ampere-turn per weber
The frequency of AC used in India is
50 Hz
100 Hz
200 Hz
1/100 Hz
At what voltage is the electric power generated at the power generating station?
11 kV
25 kV
21 kV
40 kV
A switch is always connected to the
earth wire
neutral wire
live wire
none of these
An MCB which cuts off the electricity supply in case of short-circuiting or overloading works on the :
chemical effect of current
heating effect of current
magnetic effect of current
electroplating effect of current
At the time of short circuit, the current in the circuit :
reduces substantially
does not change
increases heavily
varies continuously
According to International convention of colour coding of insulation of wires in a cable :
live is red, neutral is blue and earth is brown
live is red, neutral is green and earth is black
live is brown, neutral is blue and earth is black
live is brown, neutral is light blue and earth is green