Magnetic Dipole Moment of a Revolving Electron

Two mutually perpendicular lines are drawn on a table. Two small magnets, whose magnetic moments are $0.108$ and $0.192 \mathrm{J} {\mathrm{T}}^{-1}$, are placed on these lines. If the distance of the point of intersection of these lines be respectively $30$ and $40$$\mathrm{cm}$ from these magnets, then find the resultant magnetic field at the point of intersection.

A bar-magnet of magnetic moment $1.5 \mathrm{A} {\mathrm{m}}^2$, when suspended perpendicular to a magnetic field, is acted upon by a couple of $0.24 \mathrm{N}-\mathrm{m}$, What is the magnitude of the magnetic field?

Define magnetic dipole moment in terms of current and area of a loop and in terms of pole strength of a magnetic dipole. Write unit of magnetic dipole and pole strength.

If it is assumed that earth’s magnetism is due to the presence of a large current-loop within the earth, then how will the plane of this loop be situated, and what will be the direction of current in it?

It is claimed that the earth’s magnetic field approximates the field due to a magnetic dipole of moment $8\times {10}^{22}\mathrm{A}/{\mathrm{m}}^2$ placed at the centre of the earth. Check the order of magnitude of the magnetic field.

Interstellar space has an extremely weak magnetic field $\left(\approx {10}^{-12}\mathrm{T}\right)$. Can there be any significant consequence of such a weak field?

Geologists claim that besides the main magnetic $N-S$ poles, there are several local poles on the earth’s surface oriented in different directions. How is it possible?

The earth’s field deviates from its dipole shape at distances larger than about $30000 \mathrm{km}$ above the earth. Why?

Define magnetic moment of a magnet (dipole) and give its SI unit. Is it a vector or a scalar quantity?

A short bar-magnet placed with its axis making an angle $\mathrm{\theta }$ with a uniform magnetic field $\overrightarrow{\mathrm{B}}$ experienced
a torque$\overrightarrow{\mathit{\tau }}$ . What is the magnitude of the magnetic moment of the magnet?

State the SI unit of magnetic dipole moment, indicating its direction.