Write formula for moving charge $\mathrm{q}$ in magnetic field.
Three long current carrying wires $P, Q$ and $R$ placed perpendicular to plane of the paper. Magnetic force per unit length on wire $'R'$ is
A conducting loop carrying a current $I$ is placed in a uniform magnetic field pointing into the plane of the paper as shown. The loop will have a tendency to
A metallic loop is placed in a magnetic field. If a current is passed through it, then
Three long straight wires are connected parallel to each other across a battery of negligible internal resistance. The ratio of their resistances are $3 : 4 : 5$. What is the ratio of distances of middle wire from the others if the net force experienced by it is zero
A square loop $ABCD$, carrying a current $i,$ is placed near and coplanar with a long straight conductor $XY$ carrying a current $I,$ the net force on the loop will be