The law that the induced e.m.f. and current always oppose the cause producing them is due to____________?

Related Mcqs:

1. Which of the following circuit elements will oppose the change in circuit current ?

   A. Capacitance
   B. Inductance
   C. Resistance
   D. All of the above

2. Which circuit element(s) will oppose the change in circuit current ?

   A. Resistance only
   B. Inductance only
   C. Capacitance only
   D. Inductance and capacitance

3. 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

4. emf induced in a circuit according to Faradays law depends on the_____________?

   A. maximum magnetic flux
   B. rate of change of magnetic flux
   C. change in magnetic flux
   D. initial magnetic flux

5. The property of coil by which a counter e.m.f. is induced in it when the current through the coil changes is known as__________?

   A. self-inductance
   B. mutual inductance
   C. series aiding inductance
   D. capacitance

6. An e.m.f. of 16 volts is induced in a coil of inductance 4H. The rate of change of current must be______________?

   A. 64 A/s
   B. 32 A/s
   C. 16 A/s
   D. 4 A/s

7. Current changing from 8 A to 12 A in one second induced 20 volts in a coil. The value of inductance is___________?

   A. 5 mH
   B. 10 mH
   C. 5 H
   D. 10 H

8. A coil is wound on iron core which carries current I. The self-induced voltage in the coil is not affected by________________?

   A. variation in coil current
   B. variation in voltage to the coil
   C. change of number of turns of coil
   D. the resistance of magnetic path

9. The self-inductance of the coil may be defined as equal to the e.m.f. induced in volts when the current in the circuit changes at the rate of unit Weber turns

   A. Yes
   B. No

10. 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