Two long parallel wires are placed on a smooth horizontal table. They have equal and opposite charges. Work required to increase the separation between wires from a to 2a if magnitude of charge per unit length on them is λ, will be

Equal currents $\mathrm{I}$ and $\mathrm{I}$ are flowing through two infinitely-long parallel wires. What will be the magnetic field at a point mid-way between them, when the currents are in same direction,

Equal currents $\mathrm{I}$ and $\mathrm{I}$ are flowing through two infinitely-long parallel wires. What will be the magnetic field at a point mid-way between them, when the currents are in opposite directions ?

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?