A charged particle (charge q ) is moving in a circle of radius R with uniform speed v. The associated magnetic moment μ is given by :
qvR/2
qvR2
qvR
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
A charge moving with velocity v in X-direction is subjected to a field of magnetic induction in negative X – direction . As a result, the charge will
remain unaffected
start moving in a circular Y – Z plane
retard along X – axis
moving along a helical path around X – axis
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
None of the above
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
A long solenoid carrying current produces a magnetic field B along its axis. If the current is doubled and the number of turns per cm is halved, the new value of the magnetic field is :
2B
4B
B/2
B
when a charged particle moving with velocity is subjected to a magnetic field of introduction , the force on it is non – zero. This implies that
Angle between is necessarily 90o
Angle between can have any value other than 90o
Angle between can have any value other than zero and 180o
Angle between is either zero or 180o
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 coil of one turn is made of a wire of certain length and then from the same length a coil of two turns is made. If the same current is passed is both the cases, then the ratio of the magnetic induction at their centers will be
2 : 1
1 : 4
4 : 1
1 : 2