A straight wire of length 0.5 m and carrying a current of 1.2 A is placed in uniform magnetic field of induction 2 T. The magnetic field is perpendicular to the length of the wire. The force on the wire is
2. 4 N
1.2 N
3.0 N
2.0 N
Two inductors each of inductance L are connected in parallel. What is their equivalent inductance?
2L
L
L/2
L/4
A coil of resistance R and inductance L is connected to a battery of e.m.f. E volts. The final current in the coil is
A straight wire of diameter 0.5 mm carrying a current of 1 A is replaced by another wire of 1 mm diameter carrying same current. The strength of magnetic field far away is
twice the earlier value
same as the earlier value
one – half of the earlier value
one quarter of the earlier value
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 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
If a current is passed through a spring, then the spring
expands
gets compressed
remains same
None of these
A charged particle of charge q and mass m enters perpendicularly in a magnetic field Kinetic energy of the particle is E, then frequency of rotation
qB/m π
qB/2 πm
qBE/2 πm
qB/2 πE
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
A positively charged particle moving due east enters a region of uniform magnetic field directed vertically upwards. The particle will
continue to move due east
move in a circular orbit with its speed unchanged
move in a circular orbit with its speed increased
gets deflected vertically upwards
