Ch 32 Inductance 32.1 Self Inductance L = N B /I  L = -L(dI/dt) Units: Tm 2 /A = Henry Solenoid P32.4 (p.916) P32.3 (p.916)

Ch 32 Inductance 32.2 RL Circuits I =  (1 – e -t/ )/R  = L/R t=0 close I =  e -t/ /R t=0 short 

CT1: When the switch is closed, the current through the circuit exponentially approaches a value I=E/R. If we repeat this experiment with an inductor (solenoid) having twice the number of turns per unit length, the time it takes for the current to reach a value of I/2 A. increases. B. decreases. C. is the same.

Ch 32 Inductance 32.3 Energy Stored in a Magnetic Field U = LI 2 /2 u = U/Volume = B 2 /2 0 P32.25 (p.918)

Ch 32 Inductance 32.4 Mutual Inductance Read

Ch 32 Inductance 32.5 Oscillations in an LC Circuit

Ch 32 Inductance 32.5 Oscillations in an LC Circuit q = A cos(t + )  = (1/LC) 1/2 For q = Q max and i = 0 at t = 0 q = Q max cos(t) I = Q max sin(t) I max = Q max U = Q max 2 /2C = LI max 2 /2

Fig 32-17, p.1017

Fig 32-17a, p.1017

Fig 32-17b, p.1017

Fig 32-17c, p.1017

Fig 32-17d, p.1017

Fig 32-17e, p.1017

Fig 32-18, p.1018

Fig 32-19, p.1019

P32.39 (p.919) P32.43 (p.919)