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3.2.4.     Induction   <CJ chap 22.7-22.10  >

3.2.4.1. Discussion

3.2.4.1.1.     Induction also allows for the concept of a transformer which can increase or decrease AC voltage

3.2.4.1.2.      

3.2.4.2. Mathematical

3.2.4.2.1.     Self-Inductance:  the induced voltage is   V_L = - N dF_B / dt    =  - L dI/dt

3.2.4.2.1.1. The unit of inductance is the Henry (H)

3.2.4.2.2.     The equation for a transformer is V₁ / N₁ = V₂ / N₂ 

3.2.4.2.2.1. Since the transformer power input must equal power output we also have V₁I₁ = V₂I₂ 

3.2.4.2.3.     RLV Circuits:    I(t) = (V/R) (1-e^-t/t)  where   t  = L/R is the time constant of the RL circuit

3.2.4.2.4.     Energy stored in the magnetic field:  U = ½ L I²

3.2.4.3. Advanced

3.2.4.3.1.     Solve the RLV circuit:   V –RI –L dI/dt  =0 which is an inhomogeneous first order differential equation

3.2.4.3.2.