CBSE Class 10 Physics Electricity MCQs

Question. Heat produced in a current carrying wire in 5s is 60J. The same current is passed through another wire of half the resistance. The heat produced in 5s will be
(a) 30 J
(b) 60 J
(c) 15 J
(d) 120 J
Answer : A

Question. The values of mA and μA are:
(a) 10–6 and 10–9 A respectively
(b) 10–3 and 10–6 A respectively
(c) 10–3 and 10–9 A respectively
(d) 10–6 and 10–3 A respectively
Answer : B

Question. The potential at a point is 20V. The work done to bring a charge of 0.5 C from infinity to this point will be ?
(a) 10J
(b) 20J
(c) 5J
(d) 40J
Answer : A

Question. The work done in moving a unit positive charge across two points inan electric circuit is a measure of ?
(a) Potential difference
(b) Current
(c) Resistance
(d) Power
Answer : A

Question. The device used for measuring potential difference is known as ?
(a) Voltmeter
(b) Potentiometer
(c) Ammeter
(d) Galvanometer
Answer : A

Question. A current of 1 A is drawn by a filament of an electric bulb. The number of electrons passing through a cross-section of the filament in 16 seconds would be roughly:
(a) 1020
(b) 1016
(c) 1018
(d) 1023
Answer : A

Question. The free electrons of a metal
(a) Are free to move anywhere in the metal
(b) Do not collide with each other
(c) Do not collide with each other
(d) Are free to escape through the surface
Answer : A

Question. The resistivity of a certain material is 0.6 Ωm.
The material is most likely to be:
(a) an insulator
(b) a superconductor
(c) a conductor
(d) a semiconductor
Answer : D

Question. Electrical resistivity of a given metallic wire depends upon:
(a) Its length
(b) Its thickness
(c) Its shape
(d) Nature of the material
Answer : D

Question. The path of a free electron in a metal is
(a) Zig zag
(b) A straight line
(c) Circular
(d) Parabolic
Answer : A

Question. If the resistance of a certain copper wire is 1 Ω, then the resistance of a similar nichrome wire will be about:
(a) 25 Ω
(b) 30 Ω
(c) 60 Ω
((d) 45 Ω
Answer : C

Question. The current in a wire
(a) Depends on both resistance and potential difference
(b) Depends only on the potential difference applied
(c) Depends only on the resistance of the wire
(d) Does not depend on resistance and potential difference
Answer : D

Question. When there is an electric current passing through a wire, the particles moving are
(a) Electrons
(b) Protons
(c) Atoms
(d) Ions
Answer : A

Question. Unit of electric power may also be expressed as:
(a) volt-ampere
(b) kilowatt-hour
(c) watt-second
(d) joule-second
Answer : A

Question. A positive charge released from rest
(a) Moves towards the regions of lower potentia
(b) Moves towards the regions of higher potential
(c) Moves towards the regions of equal potential
(d) Does not move
Answer : A

Question. The resistance of a resistor is reduced to half of its initial value. In doing so, if other parameters of the circuit remain unchanged, the heating effects in the resistor will become:
(a) two times
(b) half
(c) one-fourth
(d) four times
Answer : A

Question. Three equal resistances when combined in series are equivalent to 90w. Their equivalent resistance when combined in parallel will be
(a) 10 W
(b) 270 W
(c) 30 W
(d) 810 W
Answer : A

Question. When a 4 V battery is connected across an unknown resistor there is a current of 100 mA in the circuit. The value of the resistance of the resister is:
(a) 4Ω
(b) 40Ω
(c) 400Ω
(d) 0.4 Ω
Answer : B

Question. An battery is used to
(a) Maintain a potential difference
(b) Measure electric current
(c) Measure electric potential
(d) Safeguard against short - circuit
Answer : A

Question. Ohms law relates potential difference with
(a) Current
(b) Time
(c) Power
(d) Energy
Answer : A

Question. Which of the following is an ohmic resistor
(a) Nichrome
(b) Diamond
(c) Germanium
(d) Diode
Answer : A

Question. At the time of short circuit, the electric current in the circuit:
(a) vary continuously
(b) does not change
(c) reduces substantially
(d) increases heavily
Answer : D

Question. Calculate the length of aluminium wire of area of cross-section 1 mm² whose resistance is 
1.56 × 10^–2 W. Given, resistivity of aluminium is 2.6 × 10^–8 W m.
(a) 60 mm
(b) 60 cm
(c) 60 m
(d) 6 m 
Answer : B

Question. Consider a simple circuit containing a battery and three identical incandescent bulbs A, B and C. Bulb A is wired in parallel with bulb B and this combination is wired in series with bulb C. What would happen to the brightness of the other two bulbs if bulb A were to burn out? 
(a) Only bulb B would get brighter.
(b) Both A and B would get brighter.
(c) Bulb B would get brighter and bulb C would get dimmer.
(d) There would be no change in the brightness of either bulb B or bulb C
Answer : C

Question. The equivalent resistance between the points A and B as shown in the figure is 

(a) 6 W
(b) 8 W
(c) 16 W
(d) 24 W
Answer : B

Question. A piece of aluminium of finite length is drawn or stretched such that to reduce its diameter to one fourth its original value, its resistance will become 
(a) 256 times
(b) four times
(c) eight times
(d) sixteen times
Answer : A

Question. The normal positions of the pointers of the two ammeters A₁ and A₂, and two voltmeters V₁ and V₂ available in the laboratory are shown in figure. For verifying Ohm’s law the student should select 9 D
(a) ammeter A₁ and voltmeter V₁
(b) ammeter A₁ and voltmeter V₂
(c) ammeter A₂ and voltmeter V₁
(d) ammeter A₂ and voltmeter V₂
Answer : D

Question. In an electrical circuit, three incandescent bulbs A, B and C of rating 40 W, 60 W and 100 W respectively are connected in parallel to an electric source. Which of the following is likely to happen regarding their brightness? 
(a) Brightness of all the bulbs will be the same
(b) Brightness of bulb A will be the maximum
(c) Brightness of bulb B will be more than that of A
(d) Brightness of bulb C will be less than that of B
Answer : C

Question. The effective resistance between A and B is 

(a) r₁ + r₂
(b) r1 − r2
(c) 1/r1 + 1/r₂
(d) r₁ r₂/r1 + r₂
Answer : D

Question. There are three copper wires of lengths and cross-sectional areas (L, A), (2 L, A/2), (L/2, 2 A). Resistivity is 
(a) minimum of wire of cross-sectional area A/2
(b) minimum of wire of cross-sectional area A
(c) minimum of wire of cross-sectional area 2A
(d) same in all the three cases.
Answer : D

Question. 10,000 alpha-particles per minute are passing through a straight tube of radius r. 
The resulting electric current is approximately
(a) 0.5 × 10–16 A
(b) 2 × 1012 A
(c) 0.5 × 1012 A
(d) 2 × 10–12 A
Answer : A

Question. For ensuring dissipation of same energy in all three resistors (R₁, R₂, R₃) connected as shown in figure, their value must be related as 
 
(a) R₁ = R₂ = R₃
(b) R₂ = R₃ and R₁ = 4R₂
(c) R₂ = R₃ and R₁ = 1/4 R₂
(d) R₁ = R₂ + R₃
Answer : C

Question. To determine the equivalent resistance of a series combination of two resistors R₁ and R₂, a student arrange the following set up. 

Which one of the following statements will be true for this circuit ? It gives
(a) incorrect reading for current I as well as potential difference V
(b) correct reading for current I but incorrect reading for potential difference V
(c) correct reading for potential difference V but incorrect reading for current I
(d) correct reading for both I and V.
Answer : B

Question. If current through a resistance is increased by 100%, simultaneously reducing resistance value to 25%, the new power dissipated will be 
(a) same
(b) increased by 100%
(c) decreased by 400%
(d) increased by 400%
Answer : A

Question. The amount of heat energy produced in 5 minutes by an electric heater rated at 1000 W is 
(a) 2 × 105 J
(b) 3 × 105 J
(c) 4 × 105 J
(d) 300 J
Answer : B

Question. A current of 4.8 A is flowing in a conductor. 
The number of electrons passing per second through the conductor will be
(a) 3 × 10²⁰
(b) 76.8 × 10²⁰
(c) 7.68 × 10^–19
(d) 3 × 10¹⁹
Answer : D

Question. In an experiment on finding equivalent resistance of two resistors in series, four students draw up circuits. Which one is correct? 


Answer : C

Question. Two metallic wires A and B are connected in series. Wire A has length l and radius r, while wire B has length 2l and radius 2r. If both the wires are of same material then find the ratio of the total resistance of series combination to the resistance of the wire A. 
(a) 3/4
(b) 3/2
(c) 6/2
(d) 6/5
Answer : B

Question. What is immaterial for an electric fuse wire? 
(a) Its specific resistance
(b) Its radius
(c) Its length
(d) Current flowing through it
Answer : C

Question. The resistivity does not change if 
(a) the material is changed
(b) the temperature is changed
(c) the shape of the resistor is changed
(d) both material and temperature are changed.
Answer : C

Question. Choices for the correct combination of elements from column-I and column-II are given as options (a), (b), (c) and (d) out of which one is correct? 
Column-I Column-II
(P) Current 1. ohm
(Q) Potential 2. ampere
(R) Resistance 3. ohm m
(S) Resistivity 4. volt
(a) P-2, Q-4, R-1, S-3
(b) P-3, Q-4, R-2, S-1
(c) P-4, Q-3, R-1, S-2
(d) P-2, Q-1, R-4, S-3
Answer : A

Question. A 100 W bulb B₁, two 60 W bulbs B₂ and B₃ are connected to a 250 V source as shown. If W₁, W₂ and W₃ are powers of the bulbs, then 

(a) W₁ > W₂ = W₃
(b) W₁ > W₂ > W₃
(c) W₁ < W₂ = W₃
(d) W₁ < W₂ < W₃.
Answer : D

Question. The resistivity of a wire depends on
(a) Length, material and area of cross section
(b) Area of cross section
(c) Length
(d) Material
Answer : A

Question. For which of the following substances, resistance decreases with temperature
(a) Carbon
(b) Mercury
(c) Platinum
(d) Copper
Answer : A

Question. Four cells each of e.m.f E are joined in parallel to form a battery. The equivalent e.m.f of the battery will be
(a) E
(b) 4 E
(c) E / 4
(d) E = 0
Answer :A

Question. A cylindrical conductor of length l and uniform area of cross section A has resistance R.
Another conductor of length 2l and resistance R of the same material has area of cross- section:
(a) A /2
(b) 3A /2
(c) 2A
(d) 3A
Answer : C

Question. Two electric bulbs have resistances in the ratio 1:2. If they are joined in series, the energy consumed in them are in the ratio
(a) 0.0840277777777778
(b) 0.0430555555555556
(c) 0.167361111111111
(d) 0.0423611111111111
Answer : A

Question. Two bulbs of 100 W and 40 W are connected in series. The current through the 100 W bulb is 1 A. The current through the Ω0 W bulb will be:
(a) 0.4 A
(b) 0.6 A
(c) 0.8 A
(d) 1 A
Answer : D

Fill in The Blank

True/False

Question. One kilowatt is equal to 10 horse power.
Answer : False

Question. The temperature coefficient of resistance of a wire is 0.00125/cC. The resistance of the wire is 1 ohm at 300 K. The resistance will be 2 ohm at 1100 K.
Answer : False

Question. When two resistances 1 W and 3 W are connected in parallel, their equivalent resistance is less than 1 W .
Answer : True

Question. The commercial unit of electrical energy is kilowatthour (kWh).
Answer : True

Question. The quantity of charge flowing past a point multiplied by time is a current.
Answer : False

Question. The sun looks red at sunset because most of the blue light in sun rays is scattered leaving behind red yellow lights.
Answer : False

Matching Questions

Question. Match the Following

Answer : A-q, B-r, C-p, D-s

Question. 

Answer : (a) A-q, s, B-p, C-q, s D-r

Question. 

Answer : (a) A-p, B-p, C-s, q, D-r

Question. 

Answer : (b) A-p, B-q, r, C-q, D-s

Answer : (a) A-q, B-r, C-p, s, D-s

Answer : (a) A-r, B-q, C-p, D-t

Question. 

Answer : 1-(c), 2-(d), 3-(a), 4-(b)

Assertion & Reasoning Based MCQs

(a) Both assertion and reason are true, and reason is correct explanation of the assertion.
(b) Both assertion and reason are true, but reason is not the correct explanation of the assertion.
(c) Assertion is true, but reason is false.
(d) Assertion is false, but reason is true.

Question. Assertion : A current carrying wire should be charged. 
Reason : The current in a wire is due to flow of free electrons in a definite direction.
Answer : D

Question. Assertion : A voltmeter and ammeter can be used together to measure resistance and power. 
Reason : Power and resistance can be calculated from voltage and current.
Answer : A

Question. Assertion : The connecting wires are made of copper. 
Reason : The electrical conductivity of copper is high.
Answer : A

Question. Assertion : If 10 bulbs are connected in series and one bulb fused, then the remaining 9 bulbs will not work. 
Reason : Bulb of higher wattage will give less bright light.
Answer : B

Question. Assertion : The 200 W bulbs glows with more brightness than 100 W bulbs. 
Reason : A 100 watt bulb has more resistance than a 200 W bulb.
Answer : A

Question. Assertion : A bird perches on a high power line and nothing happens to the bird. 
Reason : The circuit is incomplete for the bird sitting on high power line.
Answer : A

Question. Assertion : It is advantageous to transmit electric power at high voltage. 
Reason : High voltage implies high current.
Answer : C

Question. Assertion : Electrons always move from a region of lower potential to a region of higher potential. 
Reason : Electron has a negative charge.
Answer : A

Question. Assertion : Good conductors of heat are also good conductors of electricity and vice versa. 
Reason : Mainly electrons are responsible for conduction.
Answer : A

Question. Assertion : The coil of a heater is cut into two equal halves and only one of them is used into heater. The heater will now require half the time to produce the same amount of heat. 
Reason : The heat produced is directly proportional to square of current.
Answer : B