Moving Charges and Magnetism Class 12 MCQs Questions with Answers

1. Circular loop of radius 0.0157 m carries a current 2 A. The magnetic field at the centre of the loop is :

2. Consider a wire carrying a steady current, l placed in a uniform magnetic field B perpendicular to its length. Consider the charges inside the wire. It is known that magnetic forces do no work. This implies that

3.  
A charged particle will not move with a constant velocity in a region where in,

4. Two a-particles have the ratio of their velocities as 3 : 2 on entering the field. If they move in different circular paths, then the ratio of the radii of their paths is

5. A strong magnetic field is applied on a stationary electron. Then the electron

6. Isoclinic lines are the lines joining places with :

7. The sensitivity of a tangent galvanometer can be increased by increasing:

8. The radius of the trajectory of a charged particle in a uniform magnetic field is proportional to the:

9. The conversion of a moving coil galvanometer into a voltmeter is done by

10. Which one of the following is correct statement about magnetic forces?

11. Earth’s magnetism was discovered by:

12. A current loop placed in a non-uniform magnetic field experiences

13. An electron is projected along the axis of a circular conductor carrying the same current. Electron will experience

14. A cubical region of space is filled with some uniform electric and magnetic fields. An electron enters the cube across one of its faces with velocity v and a positron enters via opposite face with velocity -v. At this instant,

15. The nature of parallel and anti-parallel currents are

16. If a charged particle moves through a magnetic field perpendicular to it

17. A current carrying power line carries current from west to east. Then the direction of the magnetic field 2 m above it is :

18. Which of the following is not correct about cyclotron?

19. The conversion of a moving coil galvanometer into a voltmeter is done by

20. A wire of length 2 metre carries a current 1 ampere, is bent to form a circle. The magnetic moment of the coil is :