In the branch $AB$ of a circuit,as shown in the figure,a current $I = (t + 2) \ A$ is flowing,where $t$ is the time in seconds. At $t = 0$,the value of $(V_A - V_B)$ will be: (in $V$)

One turn of insulated wire in the form of a planar square frame with side $l = 0.2\,m$ and resistance $1\,\Omega$ is placed in a uniform magnetic field perpendicular to the plane of the frame. The current passing through the turn when the magnetic field starts to decrease at a constant rate of $0.1\,T/s$ is....$mA$

$A$ metallic ring of radius $a$ and resistance $R$ is held fixed with its axis along a spatially uniform magnetic field whose magnitude is $B = B_0 \sin \omega t$. Gravity is neglected. Then,

$A$ conducting loop is placed in a time-varying magnetic field $B = \frac{\alpha}{t^2}$,where $\alpha$ is a positive constant. The magnetic field is directed into the plane of the loop. Determine the nature of the charge on plate $A$ of the capacitor $C$ connected in the loop.

$A$ long straight solenoid with a cross-sectional radius $a$ and number of turns per unit length $n$ has a current varying with time as $I = I_0 \sin(\omega t)$ (or simply $dI/dt = I$). The magnitude of the electric field as a function of distance $r$ from the solenoid axis is,

$A$ rectangular wire loop of sides $8 \; cm$ and $2 \; cm$ with a small cut is moving out of a region of uniform magnetic field of magnitude $0.3 \; T$ directed normal to the loop. Suppose the loop is stationary but the current feeding the electromagnet that produces the magnetic field is gradually reduced so that the field decreases from its initial value of $0.3 \; T$ at the rate of $0.02 \; T \, s^{-1}$. If the cut is joined and the loop has a resistance of $1.6 \; \Omega$,how much power is dissipated by the loop as heat? What is the source of this power?