A coil has an area of 0.05 m2 and has 800 turns. After placing the coil in a magnetic field of strength 4 x 10-5 Wbm-2, perpendicular to the field, the coil is rotated by 90o in 0.1s.The average emf induced is
zero
0.016 V
0.01 V
0.032 V
A magnet is allowed to fall through a metallic ring. During fall, its acceleration is
less than g
equal to g
greater than g
equal to 2g
A 100 mH coil carries a current of 1 A. Energy stored in the magnetic field is
0.5 J
1 J
0.1 J
0.05 J
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
20 V
40 V
10 V
80 V
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
The formation of a dipole is due to two equal and dissimilar point charges placed at a
short distance
long distance
above each other
none of the above
Energy in a current carrying coil is stored in the form of
electric field
magnetic field
dielectric strength
heat
At what distance from a long straight wire carrying a current of 12 A will the magnetic field be equal to 3 x 10-5 Wb/m2?
8 × 10-2 m
12 × 10-2 m
18 × 10-2 m
24 × 10-2 m
Both (a ) and ( b ) are correct
None of the above
Two equal electric currents are flowing perpendicular to each other as shown in the figure. AB and CD are perpendicular to each other and symmetrically placed with respect to the currents, where do we expect the resultant magnetic field to be zero?
On AB
On CD
On both AB and CD
On both OD and BO
