A. when more length for the same number of turns is provided
B. when the number of turns of the coil increase
C. when more area for each turn is provided
D. when permeability of the core increases
Related Mcqs:
- 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 - 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 - A 200 turn coil has an inductance of 12 mH. If the number of turns is increased to 400 turns, all other quantities (area, length etc.) remaining the same, the inductance will be___________?
A. 6 mH
B. 14 mH
C. 24 mH
D. 48 mH - 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 - 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 - Two coils have self-inductances of 10 H and 2 H, the mutual inductance being zero. If the two coils are connected in series, the total inductance will be_____________?
A. 6 H
B. 8 H
C. 12 H
D. 24 H - Both the number of turns and the core length of an inductive coil are doubled. Its self-inductance will be_____________?
A. unaffected
B. doubled
C. halved
D. quadrupled - 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 - 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 - Self inductance of a coil depends upon________________?
A. current flowing
B. number of turns per unit length
C. voltage produce
D. all
