Give the $SI$ unit of magnetic field from the Biot-Savart law.

$A$ circular loop of radius $0.0157\,m$ carries a current of $2.0\,A$. The magnetic field at the centre of the loop is $(\mu_0 = 4\pi \times 10^{-7}\,T\cdot m/A)$.

$A$ current of $1 \, A$ flows through an infinitely long straight wire. The magnetic field produced at a point $1 \, m$ away from it is:

$A$ small cube of side $1 \text{ mm}$ is placed at the centre of a circular loop of radius $10 \text{ cm}$ carrying a current of $2 \text{ A}$. The magnetic energy stored inside the cube is $\alpha \times 10^{-14} \text{ J}$. The value of $\alpha$ is . . . . . . . ($\mu_0 = 4\pi \times 10^{-7} \text{ Tm/A}$, $\pi = 3.14$)

Two infinitely long wires carrying currents of $8\,A$ and $6\,A$ are placed along the $X$-axis and $Y$-axis respectively. What is the magnetic field at point $P(0, 0, d)\,m$?

Two long,straight wires carry equal currents of $10 \ A$ in opposite directions as shown in the figure. The separation between the wires is $5.0 \ cm$. The magnitude of the magnetic field at a point $P$ midway between the wires is . . . . . . $\mu T$. (Given: $\mu_0 = 4\pi \times 10^{-7} \ TmA^{-1}$)