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Chapter 6. Capacitors and Inductors. Capacitors. A capacitor consists of two conducting plates separated by an insulator (or dielectric). C: capacitance. Unit: farad(F). A typical capacitor. Types: fixed variable. Polyester Mica
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Chapter 6 Capacitors and Inductors
Capacitors A capacitor consists of two conducting plates separated by an insulator (or dielectric). C: capacitance Unit: farad(F) A typical capacitor
Types: fixed variable Polyester Mica Electrolytic Ceramic Values: picofarad (pF) -- microfarad (mF) Circuit symbols for capacitors a) fixed capacitor b) variable capacitor
VAR of Capacitor Passive sign convention A capacitor is an open circuit to dc The voltage on the capacitor cannot change abruptly (in condition that i is limited)
Stored Energy in Capacitor Is capacitor active? equivalent circuit for the parallel capacitors
Inductors An inductor consists of a coil of conducting wire. L: inductance Unit: henry (H) Typical form of an inductor
Values: microhenrys(H)--- tens of henrys(H) Fixed variable Iron, steel Plastic, air Types: Circuit symbols for inductors
VAR of Inductor What happens when the current is constant? An inductor acts like a short circuit to dc. Integrating form: The current through an inductor cannot change abruptly (in condition that v is limited).
Stored Energy in Inductor Is inductor active? Equivalent circuit for the series inductors