A one metre long wire is lying at right angles to the magnetic field. A force of $1\, kg$ wt. is acting on it in a magnetic field of $0.98\, Tesla$. The current flowing in it will be....$A$
$100$
$10$
$1$
$0$
Two very long, straight, parallel conductors $A$ and $B$ carry current of $5\,A$ and $10\,A$ respectively and are at a distance of $10\,cm$ from each other. The direction of current in two conductors is same. The force acting per unit length between two conductors is: $\left(\mu_0=4 \pi \times 10^{-7}\right.$ SI unit)
A conducting circular loop of radius $r$ carries a constant current $i$. It is placed in a uniform magnetic field $\overrightarrow B $, such that $\overrightarrow B $ is perpendicular to the plane of the loop. The magnetic force acting on the loop is
Three long current carrying wires $P, Q$ and $R$ placed perpendicular to plane of the paper. Magnetic force per unit length on wire $'R'$ is
A conducting bar $PQ$ of length $l$ carrying current $I$ is suspended from a rigid support as shown in figure. A uniform magnetic field $B$ perpendicular to $PQ$ and directed away from the reader (inside the plane) is applied. If the mass of the bar is $M$ the tension in each string is
A wire carrying current $I$ is tied between points $P$ and $Q$ and is in the shape of a circular arc of radius $R$ due to a uniform magnetic field $B$ (perpendicular to the plane of the paper, shown by $\times \times \times $) in the vicinity of the wire. If the wire subtends an angle $2\theta_0$ at the centre of the circle (of which it forms an arc) then the tension in the wire is