Chapter 30
Inductance, Electromagnetic Oscillations, and AC Circuits
Our approach
• Mutual induction
• Self-inductance
• Energy in a B-field
• LR circuits
• LC circuits
• LCR series circuit
• Resonance in an LCR circuit
Mutual Inductance
• In what general situations does mutual inductance occur? (Sketch it out)
• The quantity Mutual Inductance, M21, can be considered a proportionality constant between what two quantities?
• How are the emfs related to mutual inductance in each circuit derived, and what are they?
• What maximizes mutual inductance?
Self-Inductance
• In what general situation does self-inductance occur? (Sketch it out)
• The self-inductance, L, can be considered a proportionality constant between what two quantities?
• How is the emf in the circuit related to self-inductance derived, and what is it?
• What is the circuit diagram symbol for self-inductance?
Self-Inductance (cont’d)
• How is the self-inductance figured out for a few simple cases?
Energy in a B-field
• What is the work done to increase the current from zero to I in an inductor with inductance L? Why does this make sense?
• What is the energy density in a magnetic field? Why does this make sense?
LR Circuits
• What is a simple LR circuit?
• What equation governs its behavior?
• What is its behavior (in words, graphs, mathematically)?
• If L is analogous to mass, what physical situation is analogous to an LR circuit?
LC Circuits
• What is a simple LC circuit?
• What equation governs its behavior?
• What is its behavior (in words, graphs, mathematically)?
• If L is analogous to mass, what physical situation is analogous to an LC circuit?
LCR Circuit
• What is a simple LCR circuit?
• What equation governs its behavior?
• What is its behavior (in words, graphs, mathematically)?
• If L is analogous to mass, what physical situation is analogous to an LCR circuit?
Resonance in an LCR Circuit
• In what way can resonance occur in an LCR circuit?
• How is this resonance analogous to resonance of a damped, driven harmonic oscillator?
the end