$A$ wire carrying current '$I$' along the $x$-axis has length '$L$' and is kept in a magnetic field $\vec{B} = B(\hat{i} + 2\hat{j} - 2\hat{k}) \text{ T}$. The magnitude of the magnetic force acting on the wire is:

$A$ uniform magnetic field of $1.5\; T$ exists in a cylindrical region of radius $10.0\; cm$,its direction parallel to the axis along east to west. $A$ wire carrying current of $7.0\; A$ in the north to south direction passes through this region. What is the magnitude and direction of the force on the wire if,
$(a)$ the wire intersects the axis,
$(b)$ the wire is turned from $N-S$ to northeast-northwest direction,
$(c)$ the wire in the $N-S$ direction is lowered from the axis by a distance of $6.0 \;cm?$

$A$ thin flexible wire of length $L$ is connected to two adjacent fixed points and carries a current $I$ in the clockwise direction,as shown in the figure. When the system is put in a uniform magnetic field of strength $B$ going into the plane of the paper,the wire takes the shape of a circle. The tension in the wire is

$A$ semi-circular current-carrying wire having radius $R$ is placed in the $x-y$ plane with its centre at the origin $O$. $A$ non-uniform magnetic field $\vec B = \frac{B_o x}{2R} \hat k$ (where $B_o$ is a positive constant) exists in the region. The magnetic force acting on the semi-circular wire will be along:

$A$ square loop $ABCD$ carries a current $i$ and is placed near a long straight wire $XY$ carrying a current $I$ as shown in the figure. What is the net force on the loop?

When current passing through two parallel wires flows in the same direction,the force between them is $......$,while when current passes in opposite directions through the same wires,the force between them is $......$ (attraction,repulsion).