$A$ small bar magnet is moved through a coil at a constant speed from one end to the other. Which of the following series of observations will be seen on the galvanometer $G$ attached across the coil? Three positions shown describe: $(a)$ the magnet's entry,$(b)$ the magnet is completely inside,and $(c)$ the magnet's exit.

As shown in the figure,$P$ and $Q$ are two coaxial conducting loops separated by some distance. When the switch $S$ is closed,a clockwise current $I_P$ flows in $P$ (as seen by $E$) and an induced current $I_{Q_1}$ flows in $Q$. The switch remains closed for a long time. When $S$ is opened,a current $I_{Q_2}$ flows in $Q$. Then the directions of $I_{Q_1}$ and $I_{Q_2}$ (as seen by $E$) are:

An electron is moving in a circular orbit of radius $R$ with an angular acceleration $\alpha$. At the centre of the orbit is kept a conducting loop of radius $r$ $(r \ll R)$. The $e.m.f.$ induced in the smaller loop due to the motion of the electron is

$A$ semicircle conducting ring of radius $R$ is placed in the $xy$ plane,as shown in the figure. $A$ uniform magnetic field is set up along the $x$-axis. No $emf$ will be induced in the ring if:

Which of the following is constructed on the principle of electromagnetic induction?

The unit $\text{Wb}/\Omega$ represents which physical quantity?