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
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 deutron of kinetic energy 50 keV is describing a circular orbit of radius 0.5 m in a plane perpendicular to magnetic field B. The kinetic energy of the proton that describes a circular orbit of radius 0.5 m in the same plane with the same B is
25 keV
50 keV
200 keV
100 keV
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
If a current is passed through a spring, then the spring
expands
gets compressed
remains same
None of these
Both (a ) and ( b ) are correct
None of the above
The total charge induced in a conducting loop when it is moved in magnetic field depends on
the rate of change of magnetic flux
initial magnetic flux only
the total change in magnetic flux
final magnetic flux only
A current carrying coil is subjected to a uniform magnetic field. The coil will orient so that its plane becomes
inclined at 45o to the magnetic field
inclined at any arbitrary angle to the magnetic field
parallel to the magnetic field
perpendicular to magnetic field
The magnetic induction at a point P which is at the distance of 4 cm from a long current carrying wire is 10-3 T. The field of induction at a distance 12 cm from the current will be
3.33 × 10-4 T
1.11 × 10-4 T
3 × 10-3 T
9 × 10-3 T
