Ohm's Law Multiple choice Question (Electrical Mcqs) and Answer Part 3
Electrical Engineering Objective Question and Answer
41- Total power loss in the circuit is
(A) 10 W
(B) 50.2 W
(C) 205 W
(D) 410 W
Answer: (C)
42- A resistance of 5 ohms is further drawn so that its length becomes doubled, its resistance will now be
(A) 5 ohms
(B) 7.5 ohms
(C) 10 ohms
(D) 20 ohms
Answer: (D)
43- Specific resistance of a substance measured in
(A) ohms
(B) mhos
(C) ohm-cm
(D) cm/ohm
Answer: (C)
44- A wire of resistance R has its length and cross-section both doubled. its resistance will become
(A) 4R
(B) 2R
(C) R
(D) R/4
Answer: (C)
45- Ohm's law is not applicable in all the following cases Except.
(A) Electrolytes
(B) arc lamps
(C) Insulator
(D) Vacuum ratio values
Answer: (C)
46- The element of electric heater is made of
(A) copper
(B) steel
(C) carbon
(D) nichrome
Answer: (D)
47- 5 x 10^16 electrons pass across the section of a conductor in 1 minute and 20 sec. The current flowing is
(A) 1 mA
(B) 0.1 mA
(C) 0.01 mA
(D) 10 mA
Answer: (B)
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
Answer: (A)
49- Three elements having conductance G1 , G2 and G3 are connected in parallel. Their combined conductance will be
Answer: (D)
Q 50 to 53 refer to Fig.9
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
Answer: (B)
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
Answer: (D)
52- Which of the following has negative temperature coefficient
(A) Brass
(B) Mercury
(C) Electrolytes
(D) Silver
Answer: (C)
53- All of the following has negative temperature coefficient Except
(A) Paper
(B) Gold
(C) Rubber
(D) Gutta percha
Answer: (B)
54- For the circuit shown below the current I flowing the circuit will be
(A) 1/2 A
(B) 1 A
(C) 2 A
(D) 4 A
Answer: (C)
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 the length will be
(A) 0.032 ohm
(B) 0.064 ohm
(C) 0.096 ohm
(D) 0.128 ohm
Answer: (D)
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
Answer: (A)
57- Two aluminum 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 other conductor will be
(A) 400 ohms
(B) 100 ohms
(C) 50 ohms
(D) 25 ohms
Answer: (D)
58- A nichrome wire used as heater coil has the resistance of 1 ohm/meter. 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
Answer: (C)
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
Answer: (C)
60- Variable resistors are
(A) Wire wound resistors
(B) Thin film resistors
(C) Thick film resistors
(D) all of the above
Answer: (A)
