30. Inductance.

1-2. Self & Mutual Inductance Inductance: unit : H (henry)

Mutual Inductance

Self Inductance and inductor (or choke)

Potential change

3. Magnetic Field Energy Energy stored in an inductor

4. The R-L Circuit R-C circuit Current Growth

Current graph Power in Current growth :

Current Decay Power

Problem 30.64) Find the reading in each ammeter and voltmeter at the following times a) just after switch S is closed b) after S has been closed a very long time.

Problem 30-65) Switch S is closed at t=0 with no charge initially on the capacitor. a) Find the reading of each ammeter and each voltmeter just after S is closed. b) Find the reading of each ammeter and each voltmeter after a long time has elapsed. c) Find the maximum charge on the capacitor.

5. L-C Circuit Oscillating L-C circuit Applet

Electrical oscillation Simple Harmonic oscillation

Comparison with mass-spring system

Example 30.9) 300 V was charged to a 25  F capacitor. Then, disconnected from power, connected to 10 mH inductor. Find a) frequency and period b) charge and current at t=1.2 ms.

Example 30.10) Find the magnetic and electric energy of the circuit of Example 30.9). a) t=0,b) t=1.2 ms

Problem 30.34) An L-C circuit. When i = I max, find a) Maximum energy stored in the capacitor b) How often you will have that energy?

6. L-R-C circuit L-R-C circuit Underdamped oscillation solution

Example) An L-R-C circuit. a) When R=0, what is the angular frequency? b) what value R must be to give n% decrease in angular frequency compared to the result a)