Electrical Engineering MCQ Multiple Choice Questions and Answers 46-60

(A) copper

(B) steel

(C) carbon

(D) nichrome.

47. 5xl016 electrons pass across the section of a conductor in 1 minute 20 sec. The current flowing is

(A) 1mA

(B) 0.1 mA.

(C) 0.01mA

(D) 10 mA

48.Which of the following figures represents the effect of temperature on resistance for copper ?

(A) figure A.

(B) figure B

(C) figure C

(D) figure D

49.Three elements having conductance G1, G2 and G3 are connected in parallel. Their combined conductance will be

(A) 1/( 1/G1 + 1/G2 + 1/G3)

(B) (G1G2 + G2G3 + G3G1)/(G1 + G2 + G3)

(C) 1/(G1 + G2+ G3)

(D) G1 + G2 +G3.

Questions 50 to 53 refer to Figure given below:

50.The variation of resistance of iron and some alloys with temperature is shown in figure. The variation of carbon will be represented by

(A) curve A

(B) curve B.

(C) curve C

(D) curve D

51.Curves A and B represent the properties for materials which have

(A) low resistance

(B) low conductance

(C) negative resistance

(D) negative temperature coefficient.

52.Which of the following has negative temperature coefficient ?

(A) Brass

(B) Mercury

(C) Electrolytes.

(D) Silver

53.All of the following have negative temperature coefficient EXCEPT

(A) Paper

(B) Gold.

(C) Rubber.

54.For the circuit shown below the current I flowing through the circuit will be

(A)1 / 2 A

(B) 1 A

(C) 2 A.

(D) 4 A

55.A cube of material of side 1 cm has a resistance of 0.002 ohm between its opposite faces. If the same volume of the material has a length of 8 cm and a uniform cross-section, the resistance of this length will be

(A) 0.032 ohm

(B) 0.064 ohm

(C) 0.096 ohm

(D) 0.128 ohm.

56.A standard 60 W bulb is in series with a room heater and connected across the mains. If the 60 W bulb is replaced by 100 W bulb

(A) the heater output will increase.

(B) the heater output will reduce

(C) the heater output will remains unaltered

57. Two aluminium conductors have equal length. The cross-sectional area of one conductor is four times that of the other. If the conductor having smaller cross-sectional area has a resistance of 100 ohms the resistance of other conductor will be

(A) 400 ohms

(B) 100 ohms

(C) 50 ohms

(D) 25 ohms.

58.A nichrome wire used as heater coil has the resistance of 1 ohm/m. For a heater of 1000 W at 200 V, the length of wire required will be

(A) 10 m

(B) 20 m

(C) 40 m.

(D) 80 m

59.The hot resistance of a tungsten lamp is about 10 times the cold resistance. Accordingly, cold resistance of a 100 W, 200 V lamp will be 

(A) 4000 ohm

(B)400 ohm

(C)40 ohm.

(D)4 ohm

60. Variable resistors are

(A)Wire wound resistors.

(B)Thin film resistors

(C)Thick film resistors

(D)All of the above.