The weight of an aluminum conductor as compared to a copper conductor of identical cross-section, for the same electrical resistance, is __________?
A. 50%
B. 60%
C. 100%
D. 150%
Category: Engineeeing Mcqs
__________ are the materials having electrical conductivity much less than most of the metals but much greater than that of typical insulators.
A. Varistors
B. Thermistor
C. Semi-conductors
D. Variable resistors
A rheostat differs from potentiometer in the respect that it __________?
A. has lower wattage rating
B. has higher wattage rating
C. has large number of turns
D. offers large number of tapping
The condition for the validity under Ohm’s law is that __________?
A. resistance must be uniform
B. current should be proportional to the size of the resistance
C. resistance must be wire wound type
D. temperature at positive end should be more than the temperature at negative end
When current flows through heater coil it glows but supply wiring does not glow because __________?
A. current through supply line flows at slower speed
B. supply wiring is covered with insulation layer
C. resistance of heater coil is more than the supply wires
D. supply wires are made of superior material
Temperature co-efficient of resistance is expressed in terms of __________?
A. ohms/°C
B. mhos/ohm°C
C. ohms/ohm°C
D. mhos/°C
Which method can be used for absolute measurement of resistances?
A. Lorentz method
B. Releigh method
C. Ohm’s law method
D. Wheatstone bridge method
International ohm is defined in terms of the resistance of __________?
A. a column of mercury
B. a cube of carbon
C. a cube of copper
D. the unit length of wire
