Questions in magnetism

Select	Question
	If a piece of metal was thought to be magnet, which one of the following observations would offer conclusive evidence [KCET 1994]
	The magnet can be completely demagnetized by
	A current loop placed in a magnetic field behaves like a
	A magnet when placed perpendicular to a uniform field of strength ${10^{ - 4}}Wb/{m^2}$ experiences a maximum couple of moment$4 \times {10^{ - 5}}N/m.$. What is its magnetic moment
	$Weber/m^2$ is equal to
	Two magnets, each of magnetic moment ‘M’ are placed so as to form a cross at right angles to each other. The magnetic moment of the system will be
	Two like magnetic poles of strength 10 and 40 SI units are separated by a distance 30 cm. The intensity of magnetic field is zero on the line joining them
	If a magnet of length 10 cm and pole strength 40 A-m is placed at an angle of $45^o$ in an uniform induction field of intensity $2 \times 10^{–4}T$, the couple acting on it is
	The intensity of magnetic field is H and moment of magnet is M. The maximum potential energy is
	A bar magnet of magnetic moment $200 A-m^2$ is suspended in a magnetic field of intensity 0.25 N/A-m. The couple required to deflect it through $30^o$ is