A $3\mathrm{.}25$ mm $-$long coil containing $225$ loops is wound on an iron core $($average $=1850$$0$$=1850$$0)$ along with a second coil of $115$ loops. The loops of each coil have a radius of $2\mathrm{.}40$ cmcm $.$ If the current in the first coil drops uniformly from $12\mathrm{.}0$ AA to zero in $92\mathrm{.}0$ msms $.$

Part A

Determine the mutual inductance MM$.$

M $=$ H

Part B

Determine the emf induced in the second coil.

e$2=$ V