Chapter 12 Magnetic Fields: V Mutual induction m a induced electromotance in terms of Mutual inductance Self-Inductance l Coefficient of Coupling a transients in rc circuits
Chapter 12 Magnetic Fields:V ◼ Mutual Induction M ◼ Induced Electriomotance in Terms of Mutual Inductance ◼ Self-Inductance L ◼ Coefficient of Coupling ◼ Transients in RC Circuits
12.1 Mutual Inductance M See fig 12-1
The current la in circuit a produces a magnetic field and a flux linkage Mab in the circuit b is Mab is proportional to la ab Similarly, a current Ib in b also produces a flux link age Aab in a Aba= Mbale lt can be shown that ab=M for any shape of a and b
The factor of proportionality M=M called the mutual inductance btwn the two circuits Remark M has the unit: weber/ampere= henrys M depends on the geometrical configurations of the two circuits, including their sizes, shape, orienta tions, positions M is positive if the flux d pr roduced one circuit is related to the current in the other circuit by the right-hand rule. For instance, Fig 12-1 gives a pos- itive m the directions for the currents are chosen arbitrarily
Example: M Between T wo Coaxial Solenoids See Fig. 12-2 The number of turns per meter is N, the same for both solenoids Figure 12-2 Coaxial solenoids. The two radii are taken to be approximately equal