The strength of magnetic field produced by current carrying circular wire if the number of turns of the wire increases.

The graph showing the variation of the magnetic field strength (B) with distance (r) from a long current carrying conductor is

Two long straight wires vertically pierced the plane of the paper at vertices of an equilateral triangle as shown in figure. They each carry $2 \mathrm{A},$ out of the paper. The magnetic field at the third vertex $P$ has magnitude.

A horizontal power line carries a current of $90 \mathrm{A}$ in east to west direction. What is the magnitude and direction of the magnetic field due to the current $1.5 \mathrm{m}$ below the line? Take ${\mathrm{\mu }}_0=4\mathrm{\pi }\times {10}^{-7} {\mathrm{TmA}}^{-1}$.

Two very long, straight, and insulated wires are kept at $90°$ angle from each other in $\mathrm{x}\mathrm{y}$ plane as shown in the figure.

These wires carry currents of equal magnitude $I$ , whose direction are shown in the figure. The net magnetic field at point $P$ will be:

A wire carrying current $\text{I}$ has the shape as shown in adjoining figure. Linear parts of the wire are very long and parallel to $\text{X}$ -axis while semicircular portion of radius $\text{R}$ is lying in $\text{Y}$ -$\text{Z}$ plane. Magnetic field at point $\text{O}$ is :

As shown in the figure, two infinitely long, identical wires are bent by ${90}^o$ and placed in such a way that the segments $LP$ and $QM$ are along the $x$ - axis, while segments $PS$ and $QN$ are parallel to the $y$ - axis. If $OP=OQ=4cm,$ and the magnitude of the magnetic field at $O$ is ${10}^{-4} T,$ and the two wires carry equal currents (see figure), the magnitude of the current in each wire and the direction of the magnetic field at $O$ will be $\left({\mu }_0=4\pi \times {10}^{-7}N{A}^{-2}\right):$

A circular coil of $200$ turns and of radius $20 \mathrm{cm}$ carries a current of $5\mathrm{A}$. Calculate the magnetic induction at a point along its axis, at a distance three times the radius of the coil from its centre.Use the value of ${\mathrm{\mu }}_0=4\mathrm{\pi }\times {10}^{-7}$.

Obtain an expression for the magnetic induction at a point due to an infinitely long straight conductor carrying current.