$A$ rectangular coil $ABCD$ is rotated anticlockwise with a uniform angular velocity about the axis shown in the diagram below. The axis of rotation of the coil as well as the magnetic field $B$ are horizontal. The induced $e.m.f.$ in the coil would be maximum when

$A$ fighter plane of length $20\, m$, wing span (distance from tip of one wing to the tip of the other wing) of $15\,m$ and height $5\,m$ is flying towards east over Delhi. Its speed is $240\, ms^{-1}$. The earth's magnetic field over Delhi is $5 \times 10^{-5}\,T$ with the declination angle $\, 0^\circ$ and dip of $\theta$ such that $\sin \theta = 2/3$. If the voltage developed is $V_B$ between the lower and upper side of the plane and $V_W$ between the tips of the wings, then $V_B$ and $V_W$ are close to:

$A$ conducting circular loop is placed in a uniform magnetic field of $0.04\, T$ with its plane perpendicular to the magnetic field. The radius of the loop starts shrinking at a rate of $2\, mm/s$. The induced $emf$ in the loop when the radius is $2\, cm$ is:

$A$ conducting rod of length $l$ moves with velocity $\upsilon$ in a direction parallel to a long wire carrying a steady current $I$. The axis of the rod is maintained perpendicular to the wire with the near end at a distance $r$ away as shown in the figure. Find the emf induced in the rod.

$A$ fixed rectangular conductor $ODBAC$ has negligible resistance (where $CO$ is not connected). $A$ conductor $OP$ rotates clockwise with an angular velocity $\omega$ as shown in the figure. The entire system is in a uniform magnetic field $B$ directed along the normal to the surface of the rectangular conductor $ABDC$. The conductor $OP$ is in electric contact with $ABDC$. The rotating conductor has a resistance of $\lambda$ per unit length. Find the current in the rotating conductor as it rotates by $180^{\circ}$.

$A$ certain elastic conducting material is stretched into a circular loop. It is placed with its plane perpendicular to a uniform magnetic field $B = 0.8 \, T$. When released,the radius of the loop starts shrinking at a constant rate of $dr/dt = -2 \, cm/s$. The induced emf in the loop at an instant when the radius of the loop is $r = 10 \, cm$ will be $........ mV$.