$A$ metallic wire loop of side $l = 0.1 \text{ m}$ and resistance $1 \Omega$ is moved with a constant velocity in a uniform magnetic field of $2 \text{ Wb m}^{-2}$ as shown in the figure. The magnetic field is perpendicular to the plane of the loop. The loop is connected to a network of resistors. The velocity of the loop required to have a steady current of $1 \text{ mA}$ in the loop is: (in $\text{ cm s}^{-1}$)

$A$ $20 \ m$ long uniform copper wire held horizontally is allowed to fall under gravity $(g = 10 \ m/s^2)$ through a uniform horizontal magnetic field of $0.5 \ Gauss$ perpendicular to the length of the wire. The induced $EMF$ across the wire after it travels a vertical distance of $200 \ m$ is . . . . . . $mV$.

$A$ straight conductor $0.1 \ m$ long moves in a uniform magnetic field of $0.1 \ T$. The velocity of the conductor is $15 \ m/s$ and is directed perpendicular to the field. The emf induced between the two ends of the conductor is: (in $V$)

The loop shown moves with a constant velocity $V$ in a uniform magnetic field of magnetic induction $B$ directed into the paper. The potential difference between $P$ and $Q$ is:

The figure shows an apparatus suggested by Faraday to generate electric current from a flowing river. Two identical conducting plates of length $a$ and width $b$ are placed parallel facing one another on opposite sides of the river flowing with velocity $u$ at a distance $d$ apart. Now both the plates are connected by a load resistance $R$. Then the current through the load $R$ is: (Consider the vertical component of the magnetic field produced by the earth is $B_v$ and the resistivity of river water is $\rho$.)

$A$ circular coil of radius $8.0\; cm$ and $20$ turns is rotated about its vertical diameter with an angular speed of $50\; rad \;s^{-1}$ in a uniform horizontal magnetic field of magnitude $3.0 \times 10^{-2}\; T$. Obtain the maximum and average $emf$ induced in the coil. If the coil forms a closed loop of resistance $10\; \Omega,$ calculate the maximum value of current in the coil. Calculate the average power loss due to Joule heating. Where does this power come from?