__11.The force of attraction or repulsion between two magnetic poles is inversely proportional to the square of the distance between them. This is known as__

A. Newton’s first law

B. Faraday’s first law of electromagnetic induction

C. Coulomb’s first law

**D. Coulomb’s second law**

__12. Whenever a conductor cuts magnetic flux, an emf is induced in it. This is known as__

A. Coulomb’s law

B. Joule’s law

**C. Faraday’s law**

D. Ohm’s law

__13. A law that states that the polarity of the induced voltage will oppose the change in magnetic flux causing the induction.__

A. Joule’s law

B. Faraday’s law

C. Coulomb’s law

**D. Lenz’ law**

__14. A law that states that the current in a thermionic diode varies directly with the three- halves power of anode voltage and inversely with the square of the distance between the electrodes, provided operating conditions are such that the current is limited only by the space charge.__

A. Hall’s law

B. Joule’s law

C. Child’s law

**D. Coulomb’s law**

**15. States that the ratio of the thermal conductivity is proportional to the absolute temperature for all metals.**

A. Wien’s displacement law

B. Hartleys law

**C. Hall’s law**

D. Wiedemann Franz law

__16. A law establishing the fact that the algebraic su of the rises and drops of the mmf around a closed loop of a magnetic circuit is equal to zero.__

A. Kirchhoff’s circuital law

B. Maxwell’s circuital law

**C. Ampere’s circuital law**

D. Coulomb’s circuital law

__17. The net electrical charge in an isolated system remains constant. This is known as__

**A. Law of conservation of charge**

B. Coulomb’s first law

C. Coulomb’s second law

D. Law of conservation of energy

__18. Lenz’s law is the consequence of the law of conservation of__

**A. Energy**

B. Charge

C. Field lines

D. Momentum

__19. Lenz’ law states that the direction of the induced emf and hence current__

A. Is determined by the rate of current flux

B. Is found by the right hand rule

C. Is found by the left hand rule

**D. Always opposes the cause producing it**

__20. If you hold the conductor with right hand so that the stretched thumb points in the direction of the current, then encircling fingers will give the direction of magnetic lines of force round the conductor. This is known as__

A. Left hand cork screw rule

B. Right hand cork screw rule

C. Left hand rule

**D. Right hand rule**