Two coaxial solenoids of radii $r_1$ and $r_2$ ($r_2 > r_1$) have the same length $l$ and the same number of turns $N$. If the current in the outer solenoid changes at a rate of $\frac{dI}{dt}$, what is the induced emf in the inner solenoid?

Find out the e.m.f. produced when the current changes from ${\rm{0}}$ to $1\,A$ in $10\,\,second$, given $L = 10\,\,\mu H$

In a coil when current changes from ${\rm{10}}\,{\rm{A}}$ to ${\rm{2}}\,{\rm{A}}$ in time ${\rm{0}}{\rm{.1}}\,\,{\rm{s}}$, induced emf is ${\rm{3}}.{\rm{28}}\,{\rm{V}}$. what is self –inductance of coil?

The magnetic potential energy stored in a certain induction is ${\rm{25}}{\mkern 1mu} {\mkern 1mu} \,mJ$, when the current in the inductors is ${\rm{60}}{\mkern 1mu} {\mkern 1mu} mA$. This inductors is of inductance

What is the self inductance of an air core solenoid 1 m long, diameter 0.05m, if it has 500 turns? Take ${\pi ^2} = 10.$

Two coils are at fixed locations when coil 1 has no current in coil 2 increases at the rate of $15.0\,\,A{s^{ - 1}}$ the emf is coil is 25.0 mV, when coil 2 has no current and coil ‘1’ has a current of 3.6 A, the flux linkage in coil ‘2’ is

A circular coil of radius $5\,\,cm$ has ${\rm{500}}$ turns of a wire. The approximate value of the coefficient of self induction of the coil will be

If the number of turns in a coil becomes doubled, then it self inductance will be

If number of turns in primary and secondary coils is increased to two times each, the mutual inductance

The equivalent inductance of two inductance is $2.4\,\,henry$ when connected in parallel and $10\,\,henry$ when connected in series. The difference between the two inductances is

The mutual inductance between two coils is $1.25\,\,henry$. If the current in the primary changes at the rate of $80\,\,ampere/second$, then the induced e.m.f. in the secondary is