A solenoid has $2000$ turns wound over a length of $0.3\,m$. The area of cross-section is $1.2\times10^{-3}\,m^2$. Around its central section a coil of $300$ turns is closely wound. If an initial current of $1\,A$ is reversed in $0.25\,s$. Find the emf induced in the coil.......$mV$
$24$
$32$
$48$
$20$
Two coils $X$ and $Y$ are placed in a circuit such that when a current changes $2A$ in coil $X,$ the magnetic flux changes by $0.4\,weber$ in $Y$. The value of mutual inductance of the coils....$H$
A short solenoid (length $l$ and radius $r$ with $n$ turns per unit length) lies well inside and on the axis of a very long, coaxial solenoid (length $L$, radius $R$ and $N$ turns per unit length, with $R>r$ ). Current $I$ follows in the short solenoid. Choose the correct statement.
There are two long co -axial solenoids of same length $l.$ The inner and outer coils have radii $r_1$ and $r_2$ and number of turns per unit length $n_1$ and $n_2$ respectively. The ratio of mutual inductance to the self -inductance of the inner -coil is
If a change in current of $0.01\, A$ in one coil produces a change in magnetic flux of $1.2 \times {10^{ - 2}}\,Wb$ in the other coil, then the mutual inductance of the two coils in henries is.....$H$
An electric current $i_1$ can flow either direction through loop $(1)$ and induced current $i_2$ in loop $(2)$. Positive $i_1$ is when current is from $'a'$ to $'b'$ in loop $(1)$ and positive $i_2$ is when the current is from $'c'$ to $'d'$ in loop $(2)$ In an experiment, the graph of $i_2$ against time $'t'$ is as shown below Which one $(s)$ of the following graphs could have caused $i_2$ to behave as give above.