Class 10 Science MCQ Chapter 13 Magnetic Effects of Electric Current, Class 10 Science MCQ Question Answer, Class 10 Science Multiple Choice Question Answer to each chapter is provided in the list of SCERT Science Class 10 Objective Types Question Answer so that you can easily browse through different chapters and select needs one. Class 10 Science MCQ Chapter 13 Magnetic Effects of Electric Current Question Answer can be of great value to excel in the examination.
SCERT Class 10 Science MCQ Chapter 13 Magnetic Effects of Electric Current
SCERT Class 10 General Science MCQ Chapter 13 Magnetic Effects of Electric Current Notes covers all the exercise questions in SCERT Science Textbooks. The NCERT Class 10 Science MCQ Chapter 13 Magnetic Effects of Electric Current provided here ensures a smooth and easy understanding of all the concepts. Understand the concepts behind every chapter and score well in the board exams.
Magnetic Effects of Electric Current
Chapter – 13
Multiple Choice Questions & Answers
1. Which of the following statements is incorrect for the magnetic lines of force-
(a) Two magnetic lines of force cannot intersect.
(b) Magnetic lines of force emerge from the north pole of a magnet and enter the south pole.
(c) Inside the magnet, the direction of magnetic lines of force is from the north pole to the south pole.
(d) Magnetic lines of force are some closed curve.
Ans: (c) Inside the magnet, the direction of magnetic lines of force is from the north pole to the south pole.
2. The direction of magnetic field produced around a current-carrying straight conductor depends on the direction of current through the conductor. In this case, the rule used to determine the direc- tion of magnetic field is-
(a) Right-hand thumb rule.
(b) Fleming’s left-hand rule.
(c) Fleming’s right-hand rule.
(d) None of the above.
Ans: (a) Right-hand thumb rule.
3. Which of the following statements is incorrect for the magnetic field produced by a current-carrying circular loop-
(a) Magnetic field is uniform at the centre of loop.
(b) Magnetic lines of force at the centre of the loop are parallel lines.
(c) Magnitude of the magnetic field at the centre remains same even though the number of turns of the loop is increased.
(d) Magnitude of the magnetic field inside the loop increases with the increase in current in the loop.
Ans: (c) Magnitude of the magnetic field at the centre remains same even though the number of turns of the loop is increased.
4. On which of the following factors does the force applied an a current-carrying conductor placed in a magnetic field depends-
(a) Magnitude of current through the conductor.
(b) Magnitude of the magnetic field.
(c) Length of the conductor.
(d) All of the above.
Ans: (d) All of the above.
5. The factor on which the direction of force applied on a current-carrying conductor placed in magnetic field depends is-
(a) Direction of magnetic field.
(b) Direction of current through the conductor.
(c) Both (a) and (b).
(d) None of the above.
Ans: (c) Both (a) and (b).
6. The rule which determines the direction of force on the a current-carrying conductor placed in a magnetic field is-
(a) Right-hand thumb rule.
(b) Fleming’s left-hand rule.
(c) Fleming’s right-hand rule.
(d) None of above.
Ans: (b) Fleming’s left-hand rule.
7. In the given figure an alpha particle,
(positively charged) has entered perpendicularly in a magnetic field. Direction of force acting on the alpha particle will be-
(a) To right.
(b) To left.
(c) Out of the page.
(d) Into the page.
Ans: (c) Out of the page.
8.The instrument that detects the presence of current in a circuit-
(a) Galvanometer.
(b) Ammeter.
(c) Voltmeter.
(d) None of above.
Ans: (a) galvanometer.
9. The factor on which the direction of current induced in a coil rotated in a magnetic field depends is-
(a) Direction of motion of the coil.
(b) Direction of magnetic field.
(c) Both (a) and (b).
(d) None of the above.
Ans: (c) Both (a) and (b).
10. The rule which determines the direction of current induced in a coil rotated in a magnetic field is-
(a) Fleming’s right-hand rule.
(b) Fleming’s left-hand rule.
(c) Right-hand thumb rule.
(d) None of the above.
Ans: (a) Fleming’s right-hand rule.
11. The frequency of AC in India is-
(a) 25Hz
(b) 50Hz
(c) 100Hz
(d) 5Hz
Ans: (b) 50Hz
12. The AC changes its direction in India after every –
(a) 0.01 second.
(b) 0.02 second.
(c) 1 second.
(d) 5 second.
Ans: (a) 0.01 second.
13. The potential difference between the live wire and the neutral wire in India is-
(a) 100V
(b) 200V
(c) 250V
(d) 220V
Ans: (d) 220V
14. The factor on which the value of magnetic field inside a current-carrying solenoid depends on-
(a) Current through the coil.
(b) Radius of the coil.
(c) Number of turns of the coil.
(d) All of the above.
Ans: (d) All of the above.
15. An AC generator uses-
(a) Two slip rings.
(b) A split ring.
(c) (a) or (b).
(d) None of the above.
Ans: (a) Two slip rings.
16. A DC generator uses-
(a) Two slip rings) ring.
(b) A split ring.
(c) (a) or (b)
(d) None of the above.
Ans: (b) A split ring.
17. Which one of the following acts as commutator in an electric motor-
(a) Rectangular coil
(b) Slip rings.
(c) Brush.
(d) Split ring.
Ans: (d) Split ring.
18. In an electric motor the direction of current in the coil changes once in each-
(a) Two rotations.
(b) One rotations.
(c) Half rotations.
(d) Four rotations.
Ans: (c) Half rotations.
19. For which of following angles between a conductor and a magnetic field, the force experienced by a current- carrying conductor placed in a magnetic field is the largest?
(a) 45°
(b) 90°
(c) 120°
(d) 180°
Ans: (b) 90°
20. For which of the following field, the force experienced by a current-carrying conductor placed in a mag- netic field is zero?
(a) 45°
(b) 90°
(c) 60°
(d) 180°
Ans: (d) 180°
21. A charged particle has entered at right angles into a magnetic field as shown in the figure. If the particle moves in a direction vertically out of the page in the magnetic field, then the nature of the charge on the particle is-
(a) Positive.
(b) Negative.
(c) The particle has no charge.
(d) Positive or Negative.
Ans: (a) Positive.
22. A charged particle enters a magnetic field at right angles to it as shown in the figure. If the direction of force acting on the particle is vertically into the page, the nature of charge on the particle is-
(a) Positive.
(b) Negative.
(c) The particle has no charge.
(d) Positive or Negative.
Ans: (b) Negative.
23. On the basis of which of the following principles, electric motors are constructed?
(a) The principle of electromagnetic induction.
(b) Fleming’s right-hand rule.
(c) Right-hand thumb rule.
(d) A current carrying conductor placed in a magnetic field experiences a force.
Ans: (d) A current carrying conductor placed in a magnetic field experiences a force.
24. On the basis of which of the following principles electric generators are constructed.
(a) The principle of electromagnetic induction.
(b) Fleming’s right-hand rule.
(c) Right-hand thumb rule.
(d) A current carrying conductor placed in a magnetic field experiences a force.
Ans: (a)The principle of electromagnetic induction.
25. Which of the following devices converts electrical energy into mechanical energy?
(a) Electric Generator.
(b) Galvanometer.
(c) Electric motor.
(d) Ammeter.
Ans: (c) Electric motor.
26. Which of the following devices converts mechanical energy into electrical energy?
(a) Electric Generator.
(b) Galvanometer.
(c) Electric motor.
(d) Ammeter.
Ans: (a) Electric Generator.
27. For which of the following angles between the magnetic field and the direction of motion of coil rotated in the field, current induced in the coil is the highest?
(a) 60°
(b) 90°
(c) 45°
(d) 180º
Ans: (b) 90°
28. Which of the following is used as a safety measure in domestic circuits to ensure that any leakage of current to the metallic body of an appliance does not give any severe shock to a user-
(a) Live wire.
(b) Neutral wire.
(c) Fuse.
(d) Earth wire.
Ans: (d) Earth wire.
29. Which of the following safety measures is used in domestic circuits to protect circuits from short-circuiting or over- loading?
(a) Live wire.
(b) Neutral wire.
(c) Fuse.
(d) Earth wire.
Ans: (c) Fuse.
30. An electric motor uses-
(i) Permanent magnet)
(ii) A rotating coil.
(iii) Two complete rings.
(iv) A split ring.
The correct answer is-
(a) (i), (ii), (iii)
(b) (i), (ii)
(c) only (iv)
(d) (i), (ii), (iv)
Ans: (d) (i), (ii), (iv)
31. AC generator uses-
(i) Rotating coil.
(ii) Permanent magnet.
(iii) Brushes.
(iv) Split ring.
The correct answer is-
(a) (i), (ii)
(b) (i), (ii), (iv)
(c) (i), (ii), (iii)
(d) (i), (ii),(iii), (iv)
Ans: (c) (i), (ii), (iii)
32. Which of the following is not used in a DC generator?
(a) Split ring.
(b) Two complete rings.
(c) Brushes.
(d) Magnet.
Ans: (b) Two complete rings.
33. Which of the following is not used in an AC generator?
(a) Split ring.
(b) Two complete rings.
(c) Brushes.
(d) Magnet.
Ans: (a) Split ring.
34. Which of the following is not used in a commercial motor?
(a) A coil with large number of turns.
(b) Permanent magnet.
(c) Armature.
(d) Brushes.
Ans: (b) Permanent magnet.
35. An electron has entered a magnetic field perpendicularly as shown in the figure. The direction of force acting on the electron will be-
(a) Towards right.
(b) Towards left.
(c) Out of the page.
(d) Into the page.
Ans: (d) Into the page.
Very Short & Short Type Questions and Answers:
1. What is a magnetic field?
Ans: The region around a magnet in which the force of the magnet is experienced is called a magnetic field.
2. What are the magnetic field lines or magnetic lines of force?
Ans: The lines representing the paths along which a hypothetical north pole would move in a magnetic field if it is allowed to do so are called magnetic field lines or magnetic lines of force.
3. How is the direction of magnetic field at a point in the magnetic field determined?
Ans: The direction of north pole of a compass placed at a point in a magnetic field gives the direction of magnetic field at that point.
4. Why are magnetic lines of force closed curve?
Ans: This is because, the magnetic lines of force emerge from the north pole and they merge at the south pole on the outside of a magnet, whereas the direction of magnetic lines of force inside the magnet is from the south pole to the north pole.
5. On which factor does the direction of magnetic field produced around a current-carrying straight conductor depend?
Ans: On the direction of current through the conductor.
6. Name the rule that is used to determine the direction of magnetic field produced around a current-carrying straight conductor.
Ans: Right hand thumb role.
7. What is the shape / design of the magnetic lines of force produced around a current-carrying straight conductor?
Ans: They are some concentric circles around the conductor, where the conductor passes through the centre of the circles perpendicular to their plane.
8. How will the magnetic field strength at a point in the magnetic field around a current-carrying straight conductor change if the current through the conductor is increased?
Ans: It will increase.
9. How will the magnetic field produced due to a given current through a conductor change with the increase in distance from the conductor?
Ans: It will decrease.
10. What is the nature of magnetic field at the centre of a current-carrying circular loop?
Ans: Uniform.
11. What is the nature of magnetic lines of force for a uniform magnetic field?
Ans: Parallel lines.
12. What does a uniform magnetic field mean?
Ans: A magnetic field in which magnetic field strength is same at each point is called a uniform magnetic field.
13. Why does the magnetic field inside a current- carrying circular loop increase when the number of turns of the loop is increased?
Ans: Because, current through each turn flows in the same direction and magnetic field produced due to each turn gets simply added on.
14. Why does the magnetic field inside a current- carrying circular loop increase when the number of turns of the loop is increased?
Ans: The circles representing the magnetic I lines of force become larger as they move away from the conductor. So as we ap-lproach the centre of a circular loop, the arcs of the circles appear to be some straight lines.
15. Draw the magnetic lines of force produced due to a circular loop when current flows through it.
Ans:
16. What is solenoid?
Ans: A coil of many circular turns of insulated copper wire wrapped closely in the shape of a cylinder is called a solenoid.
17. What is the nature of magnetic field inside a solenoid?
Ans: Uniform.
18. Write a use of solenoid.
Ans: A piece of magnetic material such as soft iron can be magnetised by the strong magnetic field produced by a solenoid by placing it inside the solenoid. The magnets produced in this way are called electromagnets.
19. What are electro- magnets?
Ans: A piece of magnetic material such as soft iron can be magnetised by the strong magnetic field produced by a solenoid by placing it inside the solenoid, The magnets produced in this way are called electromagnets.
20. What do we get from Fleming’s left-hand rule?
Ans: Direction of force experienced by a current-carrying conductor placed in a magnetic field.
21. Name some devices that use current-carrying conductor and magnetic field.
Ans: Electric motor, electric generator, loud speaker, microphone and measuring instruments.
22. What is an electric motor?
Ans: It is a device which converts electrical energy into mechanical energy.
23. What is a commutator?
Ans: It is a device which reverses the direction of current in a circuit.
24. Which acts as a commutator in an electric motor?
Ans: A split ring.
25. What is an armature?
Ans: In a commercial motor, a coil of insulated copper wire is wound around a core of soft iron. The soft iron core and the coil are together called an armature.
26. What is electromagnetic induction?
Ans: When number of magnetic field lines passing through a coil changes, an induced potential difference is produced in the coil which gives rise to an induced current in the coil. This phenomenon is called electromagnetic induction.
27. Which scientist discovered the technique of generating electric current from moving magnets?
Ans: Michael Faraday.
28. What does Fleming’s right-hand rule give?
Ans: The direction of induced current in a coil rotated in a magnetic field.
29. When is the induced current in a coil rotated in a magnetic field maximum?
Ans: When the direction of motion of the coil is perpendicular to the direction of magnetic field.
30. What is an electric generator?
Ans: It is a device converts mechanical energy into electrical energy.
31. What is the main difference between an electric motor and an electric generator?
Ans: An electric motor converts electric energy into mechanical energy, whereas an electric generator converts mechanical energy into electric energy.
32. What is the main difference between an AC generator and DC generator?
Ans: Two slip rings are used in an AC generator whereas a commutator(split ring) is used in a DC generator.
33. What is direct current?
Ans: The current which does not change direction over time is called a direct current.
34. What is alternating current?
Ans: The current which changes direction after a certain interval of time is called alternating current.
35. How many times does the AC change direction in one second in India?
Ans: 100 times.
36. Write an advantage of AC over DC.
Ans: As compared to DC, AC can be transmitted to long distances without much loss of energy.
37. How can an AC generator be converted into a DC generator?
Ans: By using a split ring as commutator instead of two slip rings.
38. What is the function of brush in an electric motor?
Ans: To conduct electric current from the outer circuit to the rotating coil.
39. What is the function of brushes in an electric generator?
Ans: To conduct current induced in the coil rotated in a magnetic field to the external circuit.
40. What is the function of the slip rings in electric generators?
Ans: The two slip rings get attached to the two fixed arms of the rectangular coil all the time. This maintains the alternating current nature of produced due to the station of the coil.
41. What are the three types of wires used in domestic circuits?
Ans: Live wire (with red insulation) or positive wire, neutral wire (with black insulation) or negative wire and the earth wire (with green insulation.)
42. What is an Earth wire?
Ans: It is a wire with green insulation used in our domestic circuits which is connected to the metallic bodies of the appliances and then is connected to a metal plate buried deep into the earth near the house.
43. What is short-circuiting?
Ans: Overloading can occur when the live wire and the neutral wire come into direct contact. In such a situation, the current in the circuit abruptly increases. This is called short-circuiting.
44. What do you mean by overloading?
Ans: When a cur rent higher than the permitted quantity flows through a circuit due to various reasons, the circuit is said to be overloaded.
45. On which factor does the pattern of magnetic field around a current-carrying conductor depend?
Ans: Shape of the conductor.
46. What are the current ratings for the circuit for appliances with higher power ratings such as geysers, air cooler etc and the circuit for devices with lower power ratings such as bulbs, fans etc used separately in our homes?
Ans: 15A and 5A respectively.
47. How can permanent magnets be produced using a solenoid?
Ans: By placing a piece of hard steel as the core inside a current-carrying solenoid instead of a piece of soft iron.
48. Which scientist discovered that a magnetic field is produced around a metal conductor when current is passed through it?
Ans: Hans Christian Oersted.
49. After what time does the AC change direction in India?
Ans: After every 1/100 seconds or 0.01 seconds.
50. What is the frequency of AC in India?
Ans: 50 Hz
51. What is the potential difference between the live wire and the neutral wire in our country?
Ans: 220 Volt.
