The mutual inductance of two coils is $45 \ mH$. The self-inductance of the coils are $L_1 = 75 \ mH$ and $L_2 = 48 \ mH$. The coefficient of coupling between the two coils is

The coefficient of mutual induction is $2 \ H$ and the induced e.m.f. across the secondary coil is $2 \ kV$. The current in the primary coil is reduced from $6 \ A$ to $3 \ A$. The time required for the change of current is:

Find the mutual inductance in the arrangement,when a small circular loop of wire of radius $R$ is placed inside a large square loop of wire of side $L$ $(L \gg R)$. The loops are coplanar and their centres coincide:

The coefficient of mutual inductance of two coils is $6\, mH$. If the current flowing in one is $2\, A$,then the induced $e.m.f.$ in the second coil will be:

$A$ circular loop of radius $0.3 \, cm$ lies parallel to a much bigger circular loop of radius $20 \, cm$. The centre of the small loop is on the axis of the bigger loop. The distance between their centres is $15 \, cm$. If a current of $20 \, A$ flows through the smaller loop,then the flux linked with the bigger loop is:

An alternating current of peak value $\left(\frac{2}{\pi}\right) \text{ A}$ flows through the primary coil of a transformer. The coefficient of mutual inductance between the primary and secondary coils is $1 \text{ H}$. What is the peak electromotive force (e.m.f.) induced in the secondary coil (in $\text{ V}$)? (Frequency of a.c. $= 50 \text{ Hz}$)