A long straight wire in horizontal plane carries a current of $50 \mathrm{A}$ in north to south direction. Find the magnitude and direction of magnetic field at a point $2.5 \mathrm{m}$east of the wire.

Two infinitely long insulated wires are kept perpendicular to each other. They carry currents $I_{\mathit{1}}\mathit{ }\mathit{=}\mathit{ }\mathit{2}A$ and ${\mathrm{I}}_2 = 1.5\mathrm{A}$ .

(i) Find the magnitude and direction of the magnetic field at $\mathrm{p}$.

Two infinitely long insulated wires are kept perpendicular to each other. They carry currents${\mathrm{I}}_1 = 2\mathrm{A}$ and${\mathrm{I}}_2 = 1.5\mathrm{A}$. If the direction of current be reversed in one of the wires, what would be the magnitude of the field?

An electron-beam carries a current of $5$ Microampere. Calculate the number of electrons passing through a point per second,

An electron-beam carries a current of $5$ microampere. Calculate :

(ii) magnetic field produced at a distance of $50 \mathrm{cm}.$

Two long, parallel wires are placed at a distance of $16 \mathrm{cm}$ from each other in air. Each wire has a current of $4 \mathrm{A}$. Calculate the field $\mathrm{B}$ at mid-point between them when the currents in them are

(i) in the same direction,

Two long, parallel wires are placed at a distance of$16 \mathrm{cm}$ from each other in air. Each wire has a current of $4 \mathrm{A}$. Calculate the field $\mathrm{B}$ at mid-point between them when the currents in them are

(ii) in opposite directions.