Reversing the field or the current will reverse the force on the conductor

Related Mcqs:

1. A conductor carries 125 amperes of current under 60° to a magnetic field of 1.1 tesla. The force on the conductor will be nearly______________?

   A. 50 N
   B. 120 N
   C. 240 N
   D. 480 N

2. An electric current induced within the body of a conductor when that conductor either moves through a non uniform magnetic field or in a region where there is a change in magnetic flux is called_____________?

   A. Induced current
   B. Eddy current
   C. Back emf
   D. None of the above

3. A conductor 2 meters long moves at right angles to a magnetic field of flux density 1 tesla with a velocity of 12.5 m/s. The induced e.m.f. in the conductor will be____________?

   A. 10 V
   B. 15 V
   C. 25V
   D. 50V

4. Find the force acting on a conductor 3m long carrying a current of 50 amperes at right angles to a magnetic field having a flux density of 0.67 tesla

   A. 100 N
   B. 400 N
   C. 600 N
   D. 1000 N

5. Which of the following works on torque on the current carrying conductor placed in magnetic field ?

   A. galvanometer
   B. ammeter
   C. voltmeter
   D. all of the above

6. The emf induced in a conductor of unit length moving with unit velocity at right angles to a magnetic field is equal to_____________?

   A. Magnetic flux density
   B. Torque
   C. Mutual induction
   D. Motional emf

7. Lagging of changes in the magnetization of a substance behind changes in the magnetic field as the magnetic field is varied is known as magnetic_____________?

   A. Retaintivity
   B. Permeability
   C. Flux
   D. Hysteresis

8. If current in a conductor increases then according to Lenz’s law self-induced voltage will____________?

   A. aid the increasing current
   B. tend to decrease the amount of cur-rent
   C. produce current opposite to the in-creasing current
   D. aid the applied voltage

9. The magnitude of the induced e.m.f. in a conductor depends on the______________?

   A. flux density of the magnetic field
   B. amount of flux cut
   C. amount of flux linkages
   D. rate of change of flux-linkages

10. As per Faraday’s laws of electromagnetic induction, an e.m.f. is induced in a conductor whenever it_______________?

    A. lies perpendicular to the magnetic flux
    B. lies in a magnetic field
    C. cuts magnetic flux
    D. moves parallel to the direction of the magnetic field