{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Lecture 28 - LC, RLC circuits

Lecture 28 - LC, RLC circuits - Energy in E and B fields...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Lecture 28 LC and RLC circuits. Energy in E and B fields Energy stored in a capacitor + + + + + + − − − − − − E 2 1 2 U CV = energy of the electric field 2 1 2 U LI = Energy stored in a inductor B energy of the magnetic field RC circuits (review) + + − − C R Capacitor is initially charged with Q 0 . What happens when switch is closed? Current starts at ( ) 0 0 C V Q I R RC + = = And then decays: ( ) 0 t Q I t e RC RC τ τ = = t I 0 Q RC Current through R t Q 0 Q Charge in capacitor t U 2 0 2 Q C Energy in capacitor RL circuit + + − − C L Capacitor is initially charged with Q 0 . What happens when switch is closed? • Right after it is closed: I = 0. Then current builds up. • Magnetic field is created in inductor while charge in capacitor is decreasing • Energy is being transferred form C to L (from electric to magnetic energy) As C discharges, current should decrease and stop, but inductor keeps it going, so at the end the capacitor is charged again but with the positive charge on the bottom plate.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}