$A$ vertical wire kept in the $Z-X$ plane carries a current from $Q$ to $P$ (see figure). The magnetic field due to the current will have the direction at the origin $O$ along

Two infinitely long wires each carrying the same current $i$ and pointing in $+y$ direction are placed in the $xy$ plane,at $x=-2 \ cm$ and $x=1 \ cm$. An electron is fired with speed $U$ from the origin making an angle of $+45^{\circ}$ from the $x$-axis. The force on the electron at the instant it is fired is [$B_0$ is the magnitude of the field at the origin due to the wire at $x=1 \ cm$ alone].

The magnetic induction at $O$ due to the whole length of the conductor is:

An infinitely long straight wire carrying current $I$ is bent in a planar shape as shown in the diagram. The radius of the circular part is $r$. The magnetic field at the centre $O$ of the circular loop is:

The magnetic field at the center of a circular coil carrying current '$I$' for a single turn of a given length of wire is '$B$'. The same wire is bent into a circular coil having two turns. When the same current '$I$' passes through it, the value of the magnetic field becomes:

Two mutually perpendicular insulated conducting wires carrying equal currents $I$ intersect at the origin. The resultant magnetic induction at point $P(2 \ m, 3 \ m)$ will be: