Question : Which one of the following is the resistance that must be placed parallel with 12 ? resistance to obtain a combined resistance of 4 ??
A. 8 ?
B. 6 ?
C. 4 ?
D. 2 ?
Question Listed : Electricity,
Question : Which one among the following is the correct order of power consumption for light of equal intensity?
A. Incandescent bulb < Light emitting diode < Fluorescent tube < CFL tube
B. CFL tube < Fluorescent tube < Light emitting diode < Incandescent bulb
C. Light emitting diode < CFL tube < Fluorescent tube < Incandescent bulb
D. CFL tube < Fluorescent tube < Incandescent bulb < Light emitting diode
Question Listed : Electricity,
Question : When an electrical safety fuse is rated (marked) as 16 A, it means it
A. will be blown (break) if current exceeds 16 A
B. will work if the temperature is more than 16?C
C. has a resistance of 16 ?
D. will not work if current is less than 16 A
Question Listed : Electricity,
Question : Two similarly charged bodies are kept 5 cm apart in air. If the second body is shifted away from the first by another 5 cm, their force of repulsion will be
A. reduced to one-fourth
B. quadrupled
C. halved
D. doubled
Question Listed : Electricity,
Question : Two pieces of metallic wire having equal length and equal volume placed in air have different resistances. The two wires must:
A. be of same density
B. be of different materials
C. have different temperatures
D. have different cross sections
Question Listed : Electricity,
Question : Two metallic wires A and B are of same material and have equal length. If the cross-sectional area of B is double that of A, then which one among the following is the electrical resistance of B?
A. 1/2?that of A
B. 1/4?that of A
C. 4 times that of A
D. Twice that of A
Question Listed : Electricity,
Question : Two copper wires A and B of length L and 2L respectively, have the same area of cross-section. The ratio of the resistivity of wire A to the resistivity of wire B is
A. 1/2
B. 1
C. 2
D. 4
Question Listed : Electricity,
Question : Three resistance coils of 1 ?, 2 ? and 3 ? are connected in series. If the combination is connected to a battery of 9 V, what is the potential drop across the resistance coil of 3 ? ?
A. 6.0 volt
B. 4.5 volt
C. 3.0 volt
D. 2.0 volt
Question Listed : Electricity,
Question : The specific resistance of a conducting wire depends upon
A. length of the wire only but neither on the area of cross-section of the wire nor on the material of the wire
B. material of the wire only but neither on the length of the wire nor on the area of cross-section of the wire
C. length of the wire and area of cross-section of the wire but not on the material of the wire
D. length of the wire, area of cross-section of the wire and material of the wire
Question Listed : Electricity,
Question : The resistance of a wire is 10?. If it is stretched ten times, the resistance will be
A. 1000 ?
B. 100 ?
C. 10 ?
D. 1 ?
Question Listed : Electricity,
Question : The material used for electric fuse is an alloy of tin and lead. This alloy should have
A. high specific resistance and high melting point
B. low specific resistance and low melting point
C. low specific resistance and high melting point
D. high specific resistance and low melting point
Question Listed : Electricity,
Question : The main power supply in India is at 220 V, whereas that in the US is at 110 V. Which one among the following statements in this regard is correct?
A. 110 V works better at higher latitudes
B. 110 V leads to lower power loss
C. 110 V is safer and cheaper to maintain
D. 110 V is safer but more expensive to maintain
Question Listed : Electricity,
Question : The effective resistance of three equal resistances, each of resistance r, connected in parallel, is
A. r3
B. 3r
C. r/3
D. 3/r
Question Listed : Electricity,
Question : Net charge in a current-carrying conductor is
A. either positive or negative
B. zero
C. always negative
D. always positive
Question Listed : Electricity,
Question : Microwave oven consumes less power due to:
A. small frequency as well as wavelength of radiation
B. large frequency as well as wavelength of radiation
C. short wavelength of radiation
D. small frequency of radiation
Question Listed : Electricity,