An aluminium ring $B$ faces an electromagnet $A$. The current I through $A$ can be altered. Then which of the following statement is correct?

A conducting wire frame is placed in magnetic field which is directed into the paper. The magnetic field is increasing at a constant rate. The directions of induced current in wires$A B$ and $C D$ are

The current carrying wire and the rod $AB$ are in same plane. The rod moves parallel to the wire with a velocity $v$. Which one of the following statement is true about induced emf in the rod?

A rod $AB$ slides on a $V$ shaped wire with speed $v$ as shown, such that at any time $O A=O B=l$. Magnetic field in the region is perpendicular downwards and has strength $B$, induced emf in the rod is

If given arrangement is moving towards left with speed $v$, then potential difference between $B$ and $D$ and current in the loop are respectively

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A semicircular loop of radius $R$ is rotated with an angular velocity $\mathrm{\omega }$ perpendicular to the plane of a magnetic field $B$ as shown in the figure. Emf induced in the loop is

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