# MCQs for Science Class 10 with Answers Chapter 12 Electricity

Students of class 10 Science should refer to MCQ Questions Class 10 Science Electricity with answers provided here which is an important chapter in Class 10 Science NCERT textbook. These MCQ for Class 10 Science with Answers have been prepared based on the latest CBSE and NCERT syllabus and examination guidelines for Class 10 Science. The following MCQs can help you to practice and get better marks in the upcoming class 10 Science examination

## Chapter 12 Electricity MCQ with Answers Class 10 Science

MCQ Questions Class 10 Science Electricity provided below have been prepared by expert teachers of grade 10. These objective questions with solutions are expected to come in the upcoming Standard 10 examinations. Learn the below provided MCQ questions to get better marks in examinations.

Question. Work of 14 J is done to move 2 C charge between two points on a conducting wire. What is the potential difference between the two points?
(a) 28 V
(b) 14 V
(c) 7 V
(d) 3.5 V

C

Question.  Which one among a bar of an alloy of mass 2 kg and a 3 kg iron bar of same dimension has greater resistivity?
(a) Iron bar because it has higher mass.
(b) Alloy bar because it has lower mass.
(c) Iron bar because it has the same types of atoms.
(d) Alloy bar because it has different types of atoms.

D

Question.  A fuse wire repeatedly gets burnt when used with a good heater. It is advised to use a fuse wire of
(a) more length
(c) less length

D

Question. How much more heat is produced, if the current is doubled?
(a) twice the original amount
(b) thrice the original amount
(c) four times the original amount
(d) five times the original amount

C

Question.  A circuit has a charge of 2C moving through it in 3 s. Which electrical component in the circuit, if present, will show the current?
(a) Voltmeter will show a current of 6 A.
(b) Ammeter will show a current of 0.7 A.
(c) Rheostat will show a current of 0.7 A.
(d) Resistor will show a current of 0.35 A.

B

Question.  Two bulbs are rated 40W, 220W and 60W, 220W. The ratio of their resistances will be:
(a) 4:3
(b) 3:4
(c) 2:3
(d) 3:2

D

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

B

Question. An electric toaster has a power rating of 200 W. It operates for 1 hour in the morning and 1 hour in the evening. How much does it cost to operate the toaster for 10 days at Rs 5 per kW h?
(a) Rs 20
(b) Rs 400
(c) Rs 5000
(d) Rs 10000

A

Question.  A current of 1 A is drawn by a filament of an electric bulb. 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

A

Question.  A coil in the heater consumes power P on passing current. If it is cut into halves and joined in parallel, it will consume power
(a) P
(b) P/2
(c) 2 P
(d) 4 P

D

Question.  Which of the following represents voltage?
(a) Work done / Current×Time
(b) Work done × Charge
(c) Work done×Time / Current
(d) Work done × Charge × Time

A

Question. The least resistance obtained by using 2 Ω, 4 Ω, 1 Ω and 100 Ω is
(a) < 100 Ω
(b) < 4 Ω
(c) < 1 Ω
(d) > 2 Ω

C

Question.  If R1 and R2 be the resistance of the filament of 40 W and 60 W respectively operating 220 V, then
(a) R1 < R2
(b) R2 < R1
(c) R1 = R2
(d) R1 ≥ R2

B

Question.  A cooler of 1500 W, 200 volt and a fan of 500 W, 200 volt are to be used from a household supply. The rating of fuse to be used is
(a) 2.5 A
(b) 5.0 A
(c) 7.5 A
(d) 10 A

D

Question.  Which combination of a 2 Ω resistor and 4 Ω resistor offers the least resistance to current in the circuit?
(a) Series combination, which results in a net resistance of 2 Ω.
(b) Parallel combination, which results in a net resistance of 2 Ω.
(c) Series combination, which results in a net resistance of 1.5 Ω.
(d) Parallel combination, which results in a net resistance of 0.5 Ω.

D

Question.  In an electrical circuit two resistors of 2 Ω and 4 Ω respectively are connected in series to a 6 V battery. The heat dissipated by the 4 Ω resistor in 5 s will be
(a) 5 J
(b) 10 J
(c) 20 J
(d) 30 J

C

Question.  Electrical resistivity of a given metallic wire depends upon
(a) its length
(b) its thickness
(c) its shape
(d) nature of the material

D

Question. In order to reduce electricity consumption at home, what kind of appliance should one purchase?
(a) one which draws low power
(b) one which produces less heat
(c) one which operates at a higher voltage
(d) one which draws a high amount of current

A

Question.  If n resistors each of resistance R are connected in parallel combination then their equivalent resistance is
(a) R/n2
(b) n2/R
(c) n/R
(d) R/n

D

Question.  Two resistors connected in series gives an equivalent resistance of 10 Ω. When connected in parallel, give 2.4 Ω. Then the individual resistance are
(a) each of 5 Ω
(b) 6 Ω and 4 Ω
(c) 7 Ω and 4 Ω
(d) 8 Ω and 2 Ω

B

Question. What is the relationship between resistance and current?
(a) They are directly related to each other.
(b) They are inversely related to each other.
(c) The resistance has a greater magnitude than current.
(d) The current has a greater magnitude than resistance.

B

Question.  A battery of 10 volt carries 20,000 C of charge through a resistance of 20 Ω. The work done in 10 seconds is
(a) 2 × 103 joule
(b) 2 × 105 joule
(c) 2 × 104 joule
(d) 2 × 102 joule

B

Question.  Two devices are connected between two points, say A and B in parallel. The physical quantity that will remain the same between the two points is
(a) current
(b) voltage
(c) resistance
(d) None of these

B

Question. Electric power is inversely proportional to
(a) resistance
(b) voltage
(c) current
(d) temperature

A

Question. Assertion: Conductors allow the current to flow through themselves.
Reason: They have free charge carriers.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false but R is true.
(e) Both A and R are false.

A

Question. A battery of 10 volt carries 20,000 C of charge through a resistance of 20 Ω. The work done in 10 seconds is
(a) 2 × 103 joule
(b) 2 × 105 joule
(c) 2 × 104 joule
(d) 2 × 102 joule

B

Question. The nature of the graph between potential difference and the electric current flowing through a conductor is
(a)parabolic
(b) circle
(c) straight line
(d) hyperbolic

C

Question. The resistance of hot filament of the bulb is about 10 times the cold resistance. What will be the resistance of 100 W-220 V lamp, when not in use?
(a) 48 Ω
(b) 400 Ω
(c) 484 Ω
(d) 48.4 Ω

C

Question. Resistivity of a metallic wise depends on
(a) its length
(b) its shape
(c) its thickness
(d) nature of material

D

Question. Electrical resistivity of any given metallic wire depends upon
(a) its thickness
(b) its shape
(c) nature of the material
(d) its length

C

Question: Find the current I flown in the circuit

(a) 0.05 A
(b) 5 A
(c) 50 A
(d) 500 A

A

Question: A current of 10 A flows through a conductor for 2 minutes. Find the total number of electrons flowing through the conductor.
(a) 75 × 1020
(b) 70 × 1015
(c) 60 × 1015
(d) 11 × 1012

A

Question: A current of 10 A flows through a conductor for 2 minutes. What is the amount of charge passed through the conductor?
(a) 1200 C
(b) 150 C
(c) 18 C
(d) 1.8 C

A

Question: The charge of 150 coulomb flows through a wire in one minute. What is the electric current flowing through it?
(a) 2.5 A
(b) 3.5 A
(c) 4.5 A
(d) 5.5 A

A

Question: A metal wire 80 cm long and 1.00 mm2 in cross-section has a resistance of 0.92 ohm. It’s resistivity is:
(a) 0.000 115 ohm m
(b) 0.0 115 ohm m
(c) 1.15 ohm m
(d) None of these

A

Question: Device used to measure electric current is:
(a) Ammeter
(b) Voltmeter
(c) Galvanometer
(d) Generator

A

Question: 1 Ampere is equivalent to:
(a) 1coulomb/1sec
(b)1volt/1sec
(c) 1volt meter/1sec
(d) None

A

Question: Reciprocal of resistance is called:
(a) Inductance
(b) Conductance
(c) Resistivity
(d) None of these

B

Question: Find the equivalent resistance between A and B of following circuit:

(a) 6/2
(b) 5/2 Ω
(c) 11/2Ω
(d) 1/2Ω

C

Question: The maximum resistance which can be made using four resistors each of resistance 1/2Ω W is
(a) 2Ω
(b) 1 Ω
(c) 2.5 Ω
(d) SΩ

A

Question: The proper representation of series combination of cells (Figure) obtaining maximum potential is

(a) (i)
(b) (ii)
(c) (iii)
(d) (iv)

A

Question: A current of 1 A is drawn by a filament of an electric bulb. 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

A

Question: If ‘i’ is the current flowing through a conductor of resistance ‘R’ for time ‘t’. then the heat produced (Q) is given by
(a)i2R/t
(b)iR2/t
(c) i2Rt
(d) iRt

C

Question: An electric kettle consumes 1 kW of electric power when operated at 220 V. A fuse wire of what rating must be used for it?
(a) 1 A
(b) 2 A
(c) 4 A
(d) 5 A

D

Question: A cylindrical rod is reformed to twice its length with no change in its volume. If the resistance of the rod was R, the new resistance will be
(a) R
(b) 2R
(c) 4R
(d) 8R

C

Question: A cylindrical conductor of length l and uniform area of crosssection 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

C

Question: The length of a wire is doubled and the radius is doubled. By what factor does the resistance change
(a) 4 times as large
(b) twice as large
(c) unchanged
(d) half as large

D

Question: A 24V potential difference is applied across a parallel combination of four 6 ohm resistor. The current in each resistor is
(a) 1 A
(b) 4 A
(c) 16 A
(d) 36 A

B

Question: What is the current through a 5.0 ohm resistor if the voltage across it is 10V
(a) zero
(b) 0.50 A
(c) 2.0 A
(d) 5.0 A

C

Question: A wire of length /, made of material resistivity ρ is cut into two equal parts. The resistivity of the two parts are equal to,
(a) ρ
(b) $$\frac{\rho}{2}$$
(c) 2 ρ
(d) 4 ρ

A

Question: A boy records that 4000 joule of work is required to transfer 10 coulomb of charge between two points of a resistor of 50 Ω. The current passing through it is
(a) 2 A
(b) 4 A
(c) 8 A
(d) 16 A

C

Question: A battery of 10 volt carries 20,000 C of charge through a resistance of 20 Ω. The work done in 10 seconds is
(a) 2 × 103 joule
(b) 2 × 105joule
(c) 2 × 104 joule
(d) 2 × 102 joule

B

Question: To get 2 Ω resistance using only 6 Ω resistors, the number of them required is
(a) 2
(b) 3
(c) 4
(d) 6

B

Question: The least resistance obtained by using 2 Ω, 4 Ω, 1 Ω and 100 Ω is
a) < 100 Ω
(b) < 4 Ω
(c) < 1 Ω
(d) > 2 Ω

C

Question: Two devices are connected between two points say A and B in parallel. The physical quantity that will remain the same between the two points is
(a) current
(b) voltage
(c) resistance
(d) None of these

B

Question: Calculate the current flows through the 10 Ω resistor in the following circuit.
(a) 1.2 A
(b) 0.6 A
(c) 0.2 A
(d) 2.0 A

B

Question: If R1 and R2 be the resistance of the filament of 40 W and 60 W respectively operating 220 V, then
(a) R1 < R2
(b) R2 < R1
(c) R1 = R2
(d) R1 ≥ R2

B

Question: times the cold resistance. What will be the resistance of 100 W-220 V lamp, when not in use?
(a) 48 Ω
(b) 400 Ω
(c) 484 Ω
(d) 48.4 Ω

C

Question: Two resistors are connected in series gives an equivalent resistance of 10 Ω. When connected in parallel, gives 2.4 Ω. Then the individual resistance are
(a) each of 5 Ω
(b) 6 Ω and 4 Ω
(c) 7 Ω and 4 Ω
(d) 8 Ω and 2 Ω

B

Question: A fuse wire repeatedly gets burnt when used with a good heater. It is advised to use a fuse wire of
(a) more length
(c) less length

D

Question: A cooler of 1500 W, 200 volt and a fan of 500 W, 200 volt are to be used from a household supply. The rating of fuse to be used is
(a) 2.5 A
(b) 5.0 A
(c) 7.5 A
(d) 10 A

D

Question: A coil in the heater consume power P on passing current. If it is cut into halves and joined in parallel, it will consume power
(a) P
(b) $$\frac{P}{2}$$
(c) 2P
(d) 4P

D

Question: A cell, a resistor, a key, and an ammeter are arranged as shown in the circuit diagrams. The current recorded in the ammeter will be
(a) maximum in (i)
(b) maximum in (ii)
(c) maximum in (iii)
(d) same in all the cases

D

Question: A current of 1 A is drawn by a filament of an electric bulb. 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

A

Question: A cooler of 1500 W, 200 volt and a fan of 500 W, 200 volt are to be used from a household supply. The rating of fuse to be used is
(a) 2.5 A
(b) 5.0 A
(c) 7.5 A
(d) 10 A

A

Question: What is the maximum resistance which can be made using five resistors each of 1/5 W?
(a) 1/5 Ω
(b) 10 Ω
(c) 5 Ω
(d) 1 Ω

D

Question: A student carries out an experiment and plots the V-I graph of three samples of nichrome wire with resistances R1 R2 and R3 respectively. Which of the following is hue?
(a) R1 = R2 = R3
(b) R1 > R2 > R3
(c) R3 > R2 > R1
(d) R2 > R3 > R1

C

Question: If the current I through a resistor is increased by 100 % (assume that temperature remains unchanged), the increase in power dissipated will be
(a) 100%
(b) 200%
(c) 300 %
(d) 400 %

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

C

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

C

Question: Electric potential is a:
(a) scalar quantity
(b) vector quantity
(c) neither scalar nor vector
(d) sometimes scalar and sometimes vector

A

Question: 1 mV is equal to:
(a) 10 volt
(b) 1000 volt
(c) 10-3 volt
(d) 10-6 volt

C

Question: In an electrical circuit two resistors of 2 Ω and 4 Ω respectively are connected in series to a 6 V battery. The heat dissipated by the 4 Ω resistor in 5 s will be
(a) 5 J
(b) 10 J
(c) 20 J
(d) 30 J

C

Question: Coulomb is the SI unit of:
(a) charge
(b) current
(c) potential difference
(d) resistanc

A

Question: When electric current is passed, electrons move from:
(a) high potential to low potential.
(b) low potential to high potential.
(c) in the direction of the current.
(d) against the direction of the current.

B

Question: The electrical resistance of insulators is
(a) high
(b) low
(c) zero
(d) infinitely high

D

Question. An electric kettle consumes 1 kW of electric power when operated at 220 V. A fuse wire of what rating must be used for it?
(a) 0.454A
(b) 2 A
(c) 4 A
(d) 5 A

A

Question. The type of current supplied by cell or battery is
(a) A.C
(b) D.C
(c) Both (a) and (b)
(d) None of these

B

Question. A piece of wire of resistance R is cut into five equal parts. These parts are then connected in parallel.
If the equivalent resistance of this combination is R′, then the ratio R/R′ is
(a) 1/25
(b) 1/5
(c) 5
(d) 25

D

Question. Two conducting wires of the same material and of equal lengths and equal diameter are first connected in series and then in parallel in a circuit across the same potential difference. The ratio of heat produced in series and parallel combinations would be
(a) 1:2
(b) 2:1
(c) 1:4
(d) 4:1

C

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

A

Question. When the current passing through each resistor is same, the circuit is called
(a) series circuit
(b) parallel circuit
(c) Both (a) and (b)
(d) None of these

A

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

C

Question. When resistance is doubled at constant voltage, current will become.
(a) 1/2
(b) 2 times
(c) 1/4
(d) 4 times

A

Question. Resistance in a circuit if current flowing is doubled will become
(a) double
(b) half
(c) four times
(d) remains same

D

Question. In an electrical circuit two resistors of 2 W and 4 W respectively are connected in series to a 6 V battery.
The heat dissipated by the 4 W resistor in 5 s will be
(a) 5 J
(b) 10 J
(c) 20 J
(d) 30 J

C

Question. In parallel circuit, which of the following is same across resistors
(a) Current
(b) Potential difference
(c) Resistance
(d) Resistivity

B

Question: Resistance of a metallic conductor depends on _______.
(a) its length
(b) its area of cross section
(c) its temperature
(d) All the above

D

Assertion And Reason Based Questions :

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

Question. Assertion : A torch bulb give light if operated on AC of same voltage and current as DC.
Reason : Heating effect is common to both AC and DC.

A

Question. Assertion : All electric devices shown in the circuit are ideal. The reading of each of ammeter (a) and voltmeter (V) is zero.
Reason : An ideal voltmeter draws almost no current due to very large resistance, and hence (V) and (a) will read zero.

C

Question. Assertion : The electric bulbs glows immediately when switch is on.
Reason : The drift velocity of electrons in a metallic wire is very high.

A

Question. Assertion : Bending a wire does not affect electrical resistance.
Reason : Resistance of wire is proportional to resistivity of material.

A

Question. Assertion: Tungsten metal is used for making filaments of incandescent lamps.
Reason : The melting point of tungsten is very low.

C

Question. Assertion : A conductor has +3.2X10-19C charge.
Reason : Conductor has gained 2 electrons.

C

Question. Assertion : Resistivity of material may-change with temperature.
Reason : Resistivity is a material property & independent on temperature.

C

Question. Assertion : Resistance of 50 W bulb is greater than that of 100 W.
Reason : Resistance of bulb is inversely proportional to rated power.

B

Question. Assertion : When a battery is short-circuited, the terminal voltage is zero.
Reason : In the situation of a short-circuit, the current is zero

C

Question. Assertion : Insulators do not allow flow of current through themselves.
Reason : They have no free-charge carriers.

A

Question. Assertion : Positive charge inside the cell always goes from positive terminal to the negative terminal.
Reason : Positive charge inside the cell may go from negative terminal to the positive terminal.

D

Question. Assertion : Longer wires have greater resistance and the smaller wires have lesser resistance.
Reason : Resistance is inversely proportional to the length of the wire.

C

For question numbers 1 to 3 two statements are given-one labeled as Assertion (a) and the other labeled
Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given ahead:
(a) Both ‘A’ and ‘R’ are true and ‘R’ is correct explanation of the Assertion.
(b) Both ‘A’ and ‘R’ are true but ‘R’ is not correct explanation of the Assertion.
(c) ‘A’ is true but ‘R’ is false.
(d) ‘A’ is false but ‘R’ is true.

Question. Assertion: Electric toasters are made up of alloys.
Reason: Alloys have high resistivity and do not get oxidised at high temperature.

A

Question. Assertion: The commercial unit of electrical energy is 1 kWs
Reason: 1 kWh = 3.6 × 106 J.

D

Question. Assertion: A fuse wire is always connected in parallel with the mainline.
Reason: If a current larger than the specified value flows through the circuit, fuse wire melts.

D

For question numbers 1 and 2 two statements are given-one labeled as Assertion (a) and the other labeled
Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given ahead:
(a) Both ‘A’ and ‘R’ are true and ‘R’ is correct explanation of the Assertion.
(b) Both ‘A’ and ‘R’ are true but ‘R’ is not correct explanation of the Assertion.
(c) ‘A’ is true but ‘R’ is false.
(d) ‘A’ is false but ‘R’ is true.

Question. Assertion: In parallel circuit, the current is divided into electrical gadgets, therefore, used in domestic circuit.
Reason: The resistance in parallel circuit decreases, therefore, useful.

A

Question. Assertion: Fairy lights circuit is connected in series connection.
Reason: In series combination, if one component fails then complete circuit is broken.

B

Assertion and Reasoning Based Questions

Directions : In the following questions, a statement of assertion is followed by a statement of reason. Mark the correct choice as :
(a) If both assertion and reason are true and reason is the correct explanation of assertion.
(b) If both assertion and reason are true, but reason is not the correct explanation of assertion.
(c) If assertion is true, but reason is false.
(d) If If assertion is false but reason is true

Question. Assertion : Alloys are used in making electric irons, toasters etc.
Reason : Because the resistivity of alloys is lower than its constituent metals.

C

Question. Assertion : In a circuit which is having 3 series resistors of R ohm each, the total resistance of the circuit will be 3 R.
Reason : As in parallel circuit the resultant resistance

B

Question. Assertion : An ammeter is always connected in parallel with the circuit for which current has to be measured.
Reason : As the current in a parallel circuit is not same.

D

Question. Assertion : When more current flows to an electrical equipment it shows more heating of the same.
Reason : Heat flow is directly proportional to the square of current only.

C

Question. Assertion : Bulbs are filled with inactive nitrogen and argon gases.
Reason : As there is a requirement of thermal isolation of the filament.

A

Fill in The Blanks :

Question. The resistance of a conductor depends directly on its ………., inversely on its ………., and also on the ………. of the conductor.

Length, area of cross-section, material

Question. The fuse is placed in ………. with the device.

series

Question. The resistance of a semiconductor ……… with increase in temp.

Decreases

Question. The rate of flow of electric charge is called ……….

Current

Question. In the series combination of resistors, the current is the ………. in very part of the circuit.

same

Question. Energy converted per unit charge is measured with an instrument called a (n) ……….

Voltmeter

Question. The potential difference across the ends of a resistor is ………. to the current through it, provided its ………. remains the same.

Directly proportional, temperature

Question. Fuse wire has a ……… melting point and is made of an alloy of ……… and ……… If the current in a circuit rises too high, the fuse wire ………

Question. 1 kWh = ………

3,600, 000 J

Question. If there is no current, a voltmeter connected across a resistor will register ……… voltage.

Zero

Paragraph/Table and Case Study Based Questions

1. Use the following information for questions 1(i) to 1(v):
In series circuits the energy from the supply is shared between the devices in the circuit. The more are devices added in series, the lower is the potential difference across each one. Hence the less energy is received by each one.

(i) Three resistors each of 2Ω are connected together in a triangular shape. The resistance between any two vertices will be:
(a) 4/3Ω
(b) 3/4Ω
(c) 3Ω
(d) 6Ω

A

(ii) Which arrangement of four identical resistances should be used to draw maximum energy from a cell of voltage V.

B

(iii) One kilowatt hour is equal to:
(a) 36 × 105 joules
(b) 36 × 103 joules
(c) 103 joules
(d) 105 joules

A

(iv) Two electric bulbs whose resistances are in the ratio of 1:2 are connected in parallel to a constant voltage source. The powers dissipated in them have the ratio.
(a) 1:2
(b) 1:1
(c) 2:1
(d) 1:4

C

(v) Two heater wires of equal length are first connected in series and then in parallel. The ratio of heat produced in the two cases is:
(a) 2:1
(b) 1:2
(c) 4:1
(d) 1:4

D

Creating Based Questions

Question. Rita designed a circuit in which is resistor are connected in series. Yet she is not satisfied with the series resistors because if there is a fault in some component of the circuit, then whole circuit stop working. What would be your suggestion in alternative to the resistance in series ?
Answer : To overcome the problem faced by Rita, I would suggest to connect the resistor in parallel because if the resistors are connected parallel, the whole circuit does not stop working. If the fault is with one component of the circuit, the current continues to flow through the other components of the circuit which makes the device work further.

Question. Using the following information form a pathway to explain the flow of charges inside wire. And also include information that is not mentioned below to complete it. Electrons, solid conductor, solid crystal, drift speed, steady current
Answer : In solid the atoms are very tightly packed → with little space which makes the electrons to travel → smoothly in the solid crystal similar to → a vacuum. The electrons motion in a solid conductor is → different from the empty space charges. The electrons move with average drift speed → when the steady current flows through the conductor.

Question. What would be your explanation for your friend who thinks that electrons are consumed in an electric circuit ?
Answer : The electrons are not consumed in an electric circuit. The energy provided by the electricity company is used to move electrons through electric gadgets like an electric bulb, fan and engines. We pay to electricity board for providing the energy.

Question. Brisilia designed a prototype in which she used a very sensitive electrical device. But she does not know
how to protect the sensitive electrical device from high current. Suggest her with one idea to protect the sensitive device from high current.
Answer : The suggestion to protect the sensitive electrical device from high current by using a parallel low resistor known as shunt resistor. The resistance value of shunt  resistor is very low. It is made up of the material having low temperature coefficient of resistance. It measures the electric current, alternating current or direct current.

Question. Ashwini suggested an idea that Tungsten can be used for electricity transmission. How can you explain to her that it is not the best proposal and what would be your suggestion for electricity transmission ?
Answer : Tungsten is used for making filaments since it has very high melting point. It is very bad power transmission since most of the energy is lost in the form of heat and light. The best suggestion for electricity transmission is the usage of copper and aluminium wires which are good conductors of electricity and it has high electron mobility.

2. The following apparatus is available in a laboratory which in summarised in tabular form :

(a) For what purpose an ammeter is used ?

To measure current in the circuit.

(b) If we require the maximum resistance from a number of given resistors we connect :
(i) all in series
(ii) all in parallel
(iii) less resisters in series and lens in parallel

B

(c) The best combination of voltmeter and ammeter for finding the equivalent resistance of the resistors in series would be :
(i) ammeter A1 and voltmeter V1
(ii) ammeter A1 and voltmeter V2
(iii) ammeter A2 and voltmeter V1
(iv) ammeter A2 and voltmeter V2

C

(d) For the experiment to find the equivalent resistance of the parallel combination of the two given resistor’s, the best choice would be :
(i) ammeter A1 and voltmeter V1
(ii) ammeter A1 and voltmeter V2
(iii) ammeter A2 and voltmeter V1
(iv) ammeter A2 and voltmeter V2