Which instrument works on the principle of 'Electromagnetic induction'?

$A$ square coil moves in a plane with uniform velocity $v$ parallel to its sides. $A$ magnetic field $B$ points perpendicular and into the loop. What is the induced current in the coil?

$(a)$ What is electromagnetic induction?
$(b)$ In what way can the magnitude of the induced current be increased?

$A$ magnetic compass needle is placed in the plane of paper near point $A$ as shown in the figure. In which plane should a straight current-carrying conductor be placed so that it passes through $A$ and there is no change in the deflection of the compass? Under what condition is the deflection maximum and why?

What does the direction of the thumb indicate in the Right-Hand Thumb Rule? In what way is this rule different from Fleming's Left-Hand Rule?

Two coils $C_{1}$ and $C_{2}$ are wrapped around a non-conducting cylinder. Coil $C_{1}$ is connected to a battery and a key $K$,and coil $C_{2}$ is connected to a galvanometer $G$. On pressing the key $K$,current starts flowing in the coil $C_{1}$. State your observations in the galvanometer for the following cases:
$(i)$ When key $K$ is pressed on.
$(ii)$ When current in the coil $C_{1}$ is switched off.
$(iii)$ When the current is passed continuously through coil $C_{1}$.
$(iv)$ Name and state the phenomenon responsible for the above observation. Write the name of the rule that is used to determine the direction of the induced current.