The inductance of a coil is directly proportional to
its length
the number of turns
the resistance of the coil
the square of the number of turns
During a current change from 2A to 4A in 0.05 second, 8 V of e.m.f. is developed in the coil. The coefficient of self induction is
0.1 H
0.4 H
0.8 H
0.2 H
Two inductors each of inductance L are connected in parallel. What is their equivalent inductance?
A coil of 1000 turns of wire is wound on a book and this book is lying on the table. The vertical component of earth's magnetic field is 0.6 x 10-4 T and the area of the coil is 0.05m2. The book is turned through 180o about a horizontal axis in 0.1 second. The average e.m.f. induced in the coil is
0.03 V
0.06 V
zero
0.6 V
In a current carrying coil the enery is stored as which of the following form ?
Electric field
Magnetic field
Dielectric strength
Heat
An aircraft has a wing span of 35 m. It is flying horizontally with a speed of 9.ms-1 and the vertical component of earth's magnetic field is 4 x 10-5T. The potential difference between the tips of the wings will be
12.6 V
0.126 V
1.26 V
0.013 V
Two coils have a mutual inductance of 0.005 H. The current changes in the first coil according to the equation I = I0 sin ωt where I0 = 10A and ω = 100π rad/sec. The maximum value of e.m.f. in the second coil is
5π volts
2π volts
π volts
4π volts
When the current changes from +2 A to -2 A in 0.05 s, and emf of 8V is induced in the coil. Calculate the coefficient of self-induction of the coil ?
0.2H
0.4H
0.8H
0.1H
The magnetic flux linked with a coil is given by the equation : Φ = 5 t2 + 3 t + 6. The induced e.m.f. in the coil in the fourth second will be
The north pole of a long horizontal bar magnet is being brought closer to vertical conducting plane along the perpendicular direction. The induced current in the conducting plane is
anticlockwise
clockwise
horizontal
vertical
