A. zero
B. negative
C. positive
D. about 2 ohms per degree
Related Mcqs:
- A 40 W bulb is connected in series with a room heater. If now 40 W bulb is replaced by 100 W bulb, the heater output will__________
A. decrease
B. increase
C. remain same
D. heater will burn out - A light bulb draws 300 mA when the voltage across it is 240 V. The resistance of the light bulb is___________?
A. 400 Q
B. 600 Q
C. 800 Q
D. 1000 Q - The filament of an electric bulb is made of______________?
A. carbon
B. aluminium
C. tungsten
D. nickel - An electric filament bulb can be worked from____________?
A. D. C. supply only
B. A. C. supply only
C. Battery supply only
D. All above - 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 ?
A. 18 Q
B. 36 Q
C. 48 Q
D. 64 Q - The resistance of a copper wire 200 m long is 21 Q. If its thickness (diameter) is 0.44 mm, its specific resistance is around_______________?
A. 1.2 x 10~8 Q-m
B. 1.4 x 10~8 Q-m
C. 1.6 x 10″”8 Q-m
D. 1.8 x 10″8 Q-m - Which of the following materials has a negative temperature co-efficient of resistance?
A. Copper
B. Aluminum
C. Carbon
D. Brass - Temperature co-efficient of resistance is expressed in terms of___________?
A. ohms/°C
B. mhos/ohm°C
C. ohms/ohm°C
D. mhos/°C - The resistance of a conductor of diameter d and length l is R Ω. If the diameter of the conductor is halved and its length is doubled, the resistance will be
A. R Ω
B. 2R Ω
C. 4R Ω
D. 8R Ω - If a wire conductor of 0.2 ohm resistance is doubled in length, its resistance becomes______________?
A. 0.4 ohm
B. 0.6 ohm
C. 0.8 ohm
D. 1.0 ohm
