$A$ rectangular loop of length $2.5 \ m$ and width $2 \ m$ is placed at $60^{\circ}$ to a magnetic field of $4 \ T$. The loop is removed from the field in $10 \ s$. The average emf induced in the loop during this time is

As shown in the figure,two identical conducting rings of radius $r$ are placed in a magnetic field. In figure $(a)$,the magnetic field is increasing at the rate of $0.3 \text{ T/s}$,and in figure $(b)$,the magnetic field is decreasing at the rate of $0.2 \text{ T/s}$. The direction of the current in ring $(a)$ and ring $(b)$,when observed from the top,is . . . . . .

Is relative motion an absolute condition for inducing an $emf$?

$A$ rectangular coil of $20$ turns and an area of cross-section $25 \, cm^2$ has a resistance of $100 \, \Omega$. If a magnetic field which is perpendicular to the plane of the coil changes at the rate of $1000 \, T/s$,the current in the coil is $....... \, A$.

The magnetic flux linked with a coil,in webers,is given by the equation $\phi = 3t^2 + 4t + 9$. The magnitude of the induced $e.m.f.$ at $t = 2 \ s$ will be $...... \ V$.

The figure shows certain wire segments joined together to form a coplanar loop. The loop is placed in a perpendicular magnetic field in the direction going into the plane of the figure. The magnitude of the field increases with time. $I_1$ and $I_2$ are the currents in the segments $ab$ and $cd$. Then,