Consider the situation shown in the figure. The wires $P_1Q_1$ and $P_2Q_2$ are made to slide on the rails with the same speed $5\, cm/s$. Find the electric current in the $9\,\Omega$ resistor if $(a)$ both the wires move towards the right and $(b)$ if $P_1Q_1$ moves towards the left but $P_2Q_2$ moves towards the right.

The figure shows a square loop $L$ of side $5\, cm$ which is connected to a network of resistances. The whole setup is moving towards the right with a constant speed of $1\, cm/s$. At some instant,a part of $L$ is in a uniform magnetic field of $1\, T$,perpendicular to the plane of the loop. If the resistance of $L$ is $1.7\, \Omega$,the current in the loop at that instant will be close to.....$\mu A$.

Suppose a long rectangular loop of width $w$ is moving along the $x$-direction with its left arm in a magnetic field perpendicular to the plane of the loop (see figure). The resistance of the loop is zero and it has an inductance $L$. At time $t=0$,its left arm passes the origin,$O$. If for $t \geq 0$,the current in the loop is $I$ and the distance of its left arm from the origin is $x$,then $I$ versus $x$ graph will be

$A$ straight wire of length $L$ is bent into a semicircle. It is moved in a uniform magnetic field with speed $v$ with its diameter perpendicular to the field. The induced emf between the ends of the wire is

$A$ thin semicircular conducting ring $(PQR)$ of radius $r$ is falling with its plane vertical in a horizontal magnetic field $B,$ as shown in the figure. The potential difference developed across the ring when its speed is $v,$ is

$A$ circular coil of radius $10 \, cm$ and resistance of $2 \, \Omega$ is placed with its plane perpendicular to the horizontal component of the earth's magnetic field. It is rotated about its vertical diameter through $180^{\circ}$ in $0.25 \, s$. If the magnitude of the induced emf is $3.8 \times 10^{-3} \, V$, then the number of turns of the coil is (Horizontal component of earth's magnetic field at the place is $3 \times 10^{-5} \, T$) (in $turns$)