A uniform conducting wire $ABC$ has a mass of $10 \mathrm{g}.$ A current of $2A$ flows through it. The wire is kept in a uniform magnetic field $B=2T\mathit{.}$ The acceleration of the wire will be

Two protons $A$ and $B$ move parallel to the $x$-axis in opposite directions with equal speeds $V.$ At the instant shown, the ratio of magnetic force and electric force acting on the proton $A$ is $(c=$ speed of light in vacuum)

A uniform circular wire loop is connected to the terminals of a battery. The magnetic field induction at the centre due to $ABC$ portion of the wire will be (length of $ABC=l_1,$ length of $ADC=l_2$)