Write magnetic force equation on current carrying element ${\rm{I\vec l}}$ inside magnetic field ${\rm{\vec B}}$ Write law to determine direction of magnetic field.

Wires $1$ and $2$ carrying currents ${i_1}$ and ${i_2}$respectively are inclined at an angle $\theta $ to each other. What is the force on a small element $dl$ of wire $2$ at a distance of $r$ from wire $1$ (as shown in figure) due to the magnetic field of wire $1$

Two long wires are hanging freely. They are joined first in parallel and then in series and then are connected with a battery. In both cases, which type of force acts between the two wires

Two long parallel wires carrying equal current separated by $1\,m$, exert a force of $2 \times {10^{ - 7}}\,N/m$ on one another. The current flowing through them is

A power line lies along the east-west direction and carries a current of $10\, ampere$. The force per metre due to the earth's magnetic field of ${10^{ - 4}}\,tesla$ is

A semicircular ring of radius $R$ carrying current $i$ is placed in a magnetic field of intensity $B$ so that plane of wire is perpendicular to magnetic field as shown. Net force acting on the ring is