One solenoid is centered inside another. The outer one has a length of 51.0 cm and contains 6800 coils, while the coaxial inner solenoid is 5.00 cm long and 0.160 cm in diameter and contains 21.0 coils. The current in the outer solenoid is changing at 36.5 A/s .
A) What is the mutual inductance of these solenoids? in micro H
B) Find the emf induced in the inner solenoid. in V