Level 2

A galvanometer can be changed into ammeter by connecting:

Magnetic moment of revolving electron of charge $e$ and mass $m$ in terms of angular momentum $L$ of electron is

A magnetic dipole is placed horizontally with the north pole pointing towards north. The horizontal component of earth's magnetic field is $20 \mu T.$ If the neutral point is found at a distance of $20 \mathrm{cm}$ in the plane bisecting the dipole then the magnetic moment of the dipole is
(Assume ${\mu }_0=4\pi \times {10}^{-7}$ S.I. units)

Choose the correct option.

Two long wires with no contact are placed perpendicular to each other. $i,$ and $i_2,$ are currents flowing through these wires respectively. The magnetic force on a small length $\text{'}d\text{'}$ of the second wire situated at a distance $\text{'}l\text{'}$ from, the first wire is proportional to, 

The magnetic field due to a straight long conductor of uniform cross-section of radius $a$ and carrying a steady current is represented by

Two parallel conducting wires of equal lengths placed distance $d$ apart carry currents $I_1$ and $I_2$ respectively in opposite directions. The resultant magnetic field at the midpoint of both the wires is (${\mu }_{\mathrm{o}}=$ permeability of free space.)