The coil a produces a magnetic field uon'la Its flux linking for each turn in the coil b is ab=10Nln·丌R2 and its total flux linking in the coil b is ∧ab=NbΦab=10丌B2 N'Nbla The mutual inductance is M=△ab/la=10xR2NNb uoR NaNb/la
12.2 Induced Electromotance in Terms of mutual Inductance a change in Ia induces the electromotance in b d b dt This equation is convenient to calculate vb, since M and dIa/dt are easy to measure Note that we can write aA D=fbE·d=fb(一)·dl, at where a is the vector potential at b produced by 1 Similarly, a change in Ib induces the electromotance In a
Example: The Vector potential of The Inner Solenoid The inner solenoid produces B=0 ouside itself but a change in la induces an electromotance in the outer solenoid b