In case all the flux from the current in coil 1 links with coil 2, the co-efficient of coupling will be____________?

Related Mcqs:

1. In an iron cored coil the iron core is removed so that the coil becomes an air cored coil. The inductance of the coil will_____________?

   A. increase
   B. decrease
   C. remain the same
   D. initially increase and then decrease

2. A coil of wire is arranged with its plane perpendicular to a uniform magnetic field o flux density B. when the radius of the coil increases from r1 to r2 in time Δt then what is the emf induced in the coil ?

   A. ωB/r22-r12/Δt
   B. ωB(r2-r1)2/Δt
   C. ωB(r22-r12)/Δt
   D. ωB(r22+r12)/Δt

3. A small coil lies inside a large coil. The two coils are horizontal concentric and carry currents in opposite directions. The large coil will experience______________?

   A. A torque about horizontal axis
   B. A torque about vertical axis
   C. An upward force along the axis
   D. No resultant force

4. 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

5. 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

6. 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

7. The core of a coil has a length of 200 mm. The inductance of coil is 6 mH. If the core length is doubled, all other quantities, remaining the same, the inductance will be_____________?

   A. 3 mH
   B. 12 mH
   C. 24mH
   D. 48mH

8. If the coil is wound on an iron core the flux through it will_______________?

   A. decrease
   B. become zero
   C. remain the same
   D. increase

9. The emf induced in a coil by a changing magnetic flux may have unit as______________?

   A. ms-1A
   B. ms-2A-1
   C. kgms2A-1
   D. kgm2s-1A-1

10. An average voltage of 10 V is induced in a 250 turns solenoid as a result of a change in flux which occurs in 0.5 second. The total flux change is____________?

    A. 20 Wb
    B. 2 Wb
    C. 0.2 Wb
    D. 0.02 Wb