A pivoted aluminium bar falls much more slowly through a small region containing a magnetic field then a similar bar of an insulating material. Explain.

The direction of the magnetic field lines in a region outside a bar magnet is …..

A small bar of diamagnetic substance placed in a non-magnetic field then in which direction does it move ?

A small bar of paramagnetic substance placed in a non magnetic field, then in which direction does it move ?

A small bar of ferromagnetic substance placed in a non-magnetic field then in which direction does it move ?

A bar magnet of magnetic moment m and moment of inertia I (about centre, perpendicular to length) is cut into two equal pieces, perpendicular to length. Let T be the period of oscillations of the original magnet about an axis through the mid point, perpendicular to length, in a magnetic field B. What would be the similar period T' for each piece ?

Two small and similar bar magnets have magnetic dipole moment of 1.0 Am^(2) each. They are kept in a plane in such a way that their axes are perpendicular to each other. A line drawn through the axis of one magnet passes through the centre of other magnet. If the distance between their centers is 2 m, find the magnetic field at the mid point of the line joining their centers.

What does the analog (similarity) of bar magnet's and solenoid's magnetic field lines suggest ?

Consider a metallic pipe with an inner radius of 1 cm. If a cylindrical bar magnet of radius 0.8cm is dropped through the pipe, it takes more time to come down than it takes for a similar unmagnetised cylindrical iron bar dropped through the metallic pipe. Explain.

As shown in fig. a metal ring is held horizontally and a bar magnet is dropped through the ring with its length along the axis of the ring. The acceleration of the falling magnet is ……

(a) Magnetic field lines show the direction (at every point) along which a small magnetised needle aligns at the point). Do the magnetic field lines also represent the lines of force on a moving charged particle at every point? (b) Magnetic field lines can be entirely confined within the core of a toroid, but not within a straight solenoid. Why? (c) If magnetic monopoles existed, how would the Gauss's law of magnetism be modified? (d) Does a bar magnet exert a torque on itsell due to its own field? Does one element of a current-carrying wire exert a force on another element of the same wtre? (e) Magnetic field arises due to charges in motion. Can a system have magnetic moments even though its net charge is zero?