Two free parallel wires carrying currents in opposite directions:

Heart-lung machines and artificial kidney machines employ blood pumps. $A$ mechanical pump can mangle blood cells. The figure represents an electromagnetic pump. The blood is confined to an electrically insulating tube, represented as a rectangle of width $\omega$ and height $h$. Two electrodes fit into the top and the bottom of the tube. The potential difference between them establishes an electric current through the blood, with current density $J$ over a section of length $L$. $A$ perpendicular magnetic field $B$ exists in the same region. The section of liquid in the magnetic field experiences a pressure increase given by:

$A$ wire carrying a steady current $I$ is kept in the $x$-$y$ plane along the curve $y=A \sin \left(\frac{2 \pi}{\lambda} x\right)$. $A$ magnetic field $B$ exists in the $z$-direction. The magnitude of the magnetic force on the portion of the wire between $x=0$ and $x=\lambda$ is

The force exerted by a magnetic field on a wire having length $L$ and current $I$ is perpendicular to the wire and given as $|F| = IL|B|$. An experimental plot shows $|F|$ as a function of $L$. The plot is a straight line with a slope $S = (10 \pm 1) \times 10^{-5} \ T$. The current in the wire is $I = (15 \pm 1) \ mA$. The percentage error in $B$ is:

$A$ square loop $ABCD$ of side $L$ carrying a current $I_1$ is placed at a distance $(L/3)$ from a straight conductor $XY$ carrying current $I_2$. The loop and the conductor are coplanar. The net force on the loop will be ($\mu_0$ = magnetic permeability).

$A$ power line lies along the east-west direction and carries a current of $10\, A$. The force per metre due to the earth's magnetic field of ${10^{ - 4}}\, T$ is