Physics 12 Current Electricity MCQ Question Answer – Chapter 3

CBSE and NCERT Physics 12 Current Electricity MCQ Question Answer – Chapter 3, current electricity is 3 third chapter and or physics class 12th, All the questions related to the UNIT 2 Current electricity are given here. If you want solution for NCERT Physics then you can check this link below.

In 2nd UNIT, Current Electricity there is only one chapter included in it. See chapter one and 2 MCQs here

Physics 12 Current Electricity MCQ Question Answer – Chapter 3


Ques 1: Drift velocity vd varies with the intensity of electric field E as per the relation

  • vd ∝ E
  • vd ∝ 1/E
  • vd = constant
  • vd ∝ E2

vd ∝ E

Ques 2: Dimensions of a block are 1 cm × 1 cm × 100 cm. If specific resistance of its material is 3 × 10-7 Ω m, then the resistance between the opposite rectangular faces is

  • 3 × 10-9 Ω
  • 3 × 10-7 Ω
  • 3 × 10-5 Ω
  • 3 × 10-3 Ω

3 × 10-7 Ω

Ques 3: The temperature coefficient of resistance for a wire is 0.00125 ℃-1. At 27℃ its resistance is 1 Ω. The temperature at which the resistance becomes 2 Ω is

  • 1154 K
  • 1100 K
  • 1400 K
  • 1127 K

1100 K

Ques 4: The colour sequence in a carbon resistor is red, brown, orange and silver. The resistance of the resistor is

  • 21 × 10-3 Ω ∓ 10%
  • 23 × 101 Ω ∓ 10%
  • 21 × 103 Ω ∓ 5%
  • 12 × 103 Ω ∓ 5%

21 × 10-3 Ω ∓ 10%

Ques 5: The voltage V and current I graph for a conductor at two different temperatures T1 and T2 is

  • T1 > T2
  • T1 ≈ T2
  • T1 = T2
  • T1 < T2

T1 > T2

Ques 6: From the graph between current I and voltage V as shown in identify the portion corresponding to negative resistance

  • AB
  • BC
  • CD
  • DE

CD

Ques 7: The resistivity of alloys = Ralloy ; the resistivity of constituent metals = Rmetal. Then usually

  • Ralloy = Rmetal
  • Ralloy < Rmetal
  • There is no simple relation between Ralloy and Rmetal
  • Ralloy > Rmetal

Ralloy > Rmetal

Ques 8: Masses of three wires of copper are in the ratio 1 : 3 : 5 and their lengths are in the ratio of 5 : 3 : 1. The ratio of their electrical resistances are

  • 1 : 3 : 5
  • 5 : 3 : 1
  • 1 : 15 : 125
  • 125 : 15 : 1

125 : 15 : 1

Ques 9: Two wires of same material have length L and 2 L and cross-sectional area 4 A and A respectively. The ratio of their specific resistance would be

  • 1 : 2
  • 8 : 1
  • 1 : 8
  • 1 : 1

1 : 1

Ques 10: Masses of 3 wires of same metal are in the ratio 1 : 2 : 3 and their lengths are in the ratio 3 : 2: 1. Their electrical resistance are in the ratio

  • 1 : 4 : 9
  • 9 : 4 : 1
  • 1 : 2 : 3
  • 27 : 6

27 : 6

CBSE Physics 12 Current Electricity MCQ Question Answer

Ques 11: We use alloy for making resistors, because they have :

temp. coefficient Resistivity

  • low low
  • High low
  • High low
  • low high

High low

Ques 12: For a cell potential difference is 3-6 V, when the circuit is open. If the potential difference reduces to 3 V, when cell is connected to a resistance of 5 Ω the internal resistance of cell is:

  • 1 Ω
  • 2 Ω/E
  • 4 Ω
  • 8 Ω

1 Ω

Ques 13: A cell of emf ε and internal resistance r is connected across external resistance R. the graph showing the variation of P.D. across R(i.e., V) versus R is

Ques 14: A cell supplies a current of 0.9 A through a 2 Ω resistor and a current of 0.3 A through A through 7 Ω resistor. The internal of the cell is:

  • 2.0 Ω
  • 1.5 Ω
  • 1.0 Ω
  • 0.5 Ω

0.5 Ω

Ques 15: How much word is required to carry a 6 μC charge from negative to the positive terminal of a 9 V battery ?

  • 54 × 10-3 J
  • 54 × 10-6 J
  • 54 × 10-9
  • 54 × 10-12

54 × 10-6 J

Ques 16: WSB experiment is most sensitive, when:

  • all four resistances are approximately equal
  • one of the resistance is very high as compared to other
  • one of the resistances is very low as compared to others
  • Any two resistances are equal to infority

all four resistances are approximately equal

Ques 17: In Wheatstone’s bridge, all the four arms have equal resistance R. if resistance of the galvanometer arm is also R, then equivalent resistance of the combination is

  • R
  • 2R
  • R/2
  • R/4

R

Ques 18: In a meter bridge experiment, resistance box (with R = 2 Ω) is connected in the left gap and the unknown resistance S in the right gap. If the balancing length be 40 cm, calculate the value of S

  • 2 Ω
  • 3 Ω
  • 4 Ω/li>
  • 2.5 Ω

3 Ω

Ques 19: For a cell of emf 2 V, a balance is obtained for 50 cm of the potentiometer wire. If the cell is shunted by a 2 Ω resistor and the balance is obtained across 40 cm of the wire, then the internal
resistance of the cell is:

  • 1 Ω
  • 0.5 Ω
  • 1.2 Ω
  • 2.5 Ω

0.5 Ω

Ques 20: two cells when connected in series are balanced on 8 m on a potentiometer. If the cells are connected with polarities of one of the cell is reversed, they balance on 2 m. The ratio of the emf’s of the two cells is:

  • 3 : 5
  • 5 : 3
  • 3 : 4
  • 4 : 3

5 : 3

NCERT Physics Class 12 Current Electricity Multiple Choice Questions

Ques 21: A cell of internal resistance 3 Ω and emf 10 V is connected to a uniform wire of length 500 cm and resistance 3 Ω.The potential gradient in the wire is

  • 30 mV/cm
  • 10 mV/cm
  • 20 mV/cm
  • 4 mV/cm

10 mV/cm

Ques 22: When two resistance R1 and R2 are connected in series, they consume 12 W power. when they are connected in parallel, they consume 50 W power. What is the ratio of the powers of R1 and R2 ?

  • 1/4
  • 4
  • 3/2
  • 3

3/2

Ques 23: In a Wheatston’e bridge, P = 2 Ω, Q = 2 Ω R= 2 Ω and S = 3 Ω. The resistance with which S is to be shunted in order that the bridge may be balanced is:

  • 1 Ω
  • 2 Ω
  • 4 Ω
  • 6 Ω

6 Ω

Ques 24: In a potentiometer of wire length l, a cell of emf V is balanced at a length l/3 from the positive end of the wire. For another cell of emf 1.5 V, the balancing length becomes

  • l/6
  • l/2
  • l/3
  • 2l/3

l/2

Ques 25: The heat produced by 100 W heater in 2 minutes is equal to:

  • 10.5kJ
  • 16.3 kJ
  • 12.0 kJ
  • 14.2 kJ

12.0 kJ

Ques 26: The current in the adjoing circuit will be :

  • 1/45 ampere
  • 1/15 ampere
  • 1/10 ampere
  • 1/5 ampere

1/10 ampere

Ques 27: Two resistors of resistance R1 and R2 having R1 > R2 are connected in parallel. For equivalent resistance R, the correct statement is:

  • R > R1 + R2
  • R < R1 < R2
  • R2 < R < (R1 + R2)
  • R < R1

R < R1

Ques 28: Two wires of equal diameters of resistivity p1 and p2 and length l1 and l2 respectively, are joined in series. The equivalent resistivity of the combination is:

  • p1 l1 + p2l2/(l1 + l2)
  • p1l2 + p2l1/(l1 – l2)
  • p1l2 + p2l1/(l1 + l2)
  • p1 l1 – p2l2/(l1 – l2)

p1 l1 + p2l2/(l1 + l2)

Ques 29: The potential difference between A and B in the is:

  • 32 V
  • 48 V
  • 24 V
  • 14 V

48 V

Ques 30: If the ammeter in the given circuit shown in the diagram reads 2 A, the resistance R is:

  • 1 Ω
  • 2 Ω
  • 3 Ω
  • 4 Ω

1 Ω

Physics Chapter Wise MCQ Questions and Answers

  1. Electrostatic Charges and Fields MCQ – Chapter 1
  2. Electrostatic Potential and Capacitance MCQ – Chapter 2
  3. Current Electricity MCQ Question Answer – Chapter 3
  4. Moving Charges and Magnetism MCQ – Chapter 4
  5. Magnetism And Matter MCQ – Chapter 5
  6. Electromagnetic Induction MCQ – Chapter 6
  7. MCQ Alternating Current MCQ – Chapter 7
  8. Electromagnetic Waves MCQ – Chapter 8
  9. Ray Optics And Optical Instruments MCQ – Chapter 9
  10. MCQ Wave Optics MCQ – Chapter 10
  11. Dual Nature of Radiation and Matter MCQ – Chapter 11
  12. Atoms MCQ – Chapter 12

physics 12 mcq

Physics class 12 Current Electricity MCQ test online, for other subjects are also available.

Updated: October 17, 2021 — 11:58 am

Leave a Reply

Your email address will not be published.