In the diagram shown,a time-varying non-uniform magnetic field passes through a circular region of radius $R$. The magnetic field is directed outwards and it is a function of radial distance $r$ and time $t$ according to the relation $B = B_0rt$. What is the induced electric field strength at a radial distance $R/2$ from the center?

$A$ magnetic field in a certain region is given by $\vec B = B_0 \cos(\omega t) \hat k$. $A$ coil of radius $a$ with resistance $R$ is placed in the $xy$-plane with its centre at the origin in the magnetic field (see figure). Find the magnitude and the direction of the current at $(a, 0, 0)$ at $t = \frac{\pi}{2\omega}$,$t = \frac{\pi}{\omega}$,and $t = \frac{3\pi}{2\omega}$.

Which conclusion can we obtain from the fact that an $emf$ is induced in a stationary conductor placed in a time-varying magnetic field? Discuss the characteristics of the induced electric field.

$A$ long solenoid of radius $R$ carries a time $(t)$-dependent current $I(t) = I_{0} t(1-t)$. $A$ ring of radius $2R$ is placed coaxially near its middle. During the time interval $0 \leq t \leq 1$,the induced current $(I_{R})$ and the induced $EMF$ $(V_{R})$ in the ring change as

$A$ magnetic field is changing at the rate of $4 \, T/s$ in a circular region of $5 \, cm$ radius. The value of the induced electric field at a point $P$,which is $10 \, cm$ away from the center $O$ of the region,is ..... $V/m$.

$A$ uniform magnetic field $B$ exists in a cylindrical region of radius $R = 10 \, cm$ as shown in the figure. $A$ uniform wire of length $L = 80 \, cm$ and resistance $R_{wire} = 4.0 \, \Omega$ is bent into a square frame of side length $a = 20 \, cm$ and is placed with one side along a diameter of the cylindrical region. If the magnetic field increases at a constant rate of $\frac{dB}{dt} = 0.010 \, T/s$,find the current induced in the frame.