lecture25 - Find the current through each component, and...

Info iconThis preview shows pages 1–15. Sign up to view the full content.

View Full Document Right Arrow Icon
Self-Inductance and Circuits Self-Inductance and Circuits Inductors in circuits RL circuits
Background image of page 1

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

View Full DocumentRight Arrow Icon
Inductors in Series and Parallel L T = L 1 +L 2 …. 1/L T = 1/L 1 + 1/L 2
Background image of page 2
Self-Inductance Self-Inductance dt dI L L - = ε I 2 2 1 LI U L = Potential energy stored in an inductor: Self-induced emf:
Background image of page 3

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

View Full DocumentRight Arrow Icon
RL circuits: current increasing RL circuits: current increasing The switch is closed at t =0; Find I (t). - = - = = - - I R L R L IR dt dI IR dt dI L ε 0 ε L R I Kirchoff’s loop rule:
Background image of page 4
Solution Solution R L = τ Time Constant: Note that H/ = seconds Ω (show as exercise!) ( 29 ε / 1 ) ( t e R t I - - =
Background image of page 5

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

View Full DocumentRight Arrow Icon
0 1 τ 2 τ 3 τ 4 τ 63% ε /R I t Time Constant: Current Equilibrium Value: R L = τ ( 29 ε / 1 ) ( t e R t I - - = R I =
Background image of page 6
Example 1 Calculate the inductance in an RL circuit in which R=0.5 and the current increases to one fourth of its final value in 1.5 sec.
Background image of page 7

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

View Full DocumentRight Arrow Icon
L R I RL circuits: current decreasing Assume the initial current I 0 is known. Find the differential equation for I(t) and solve it.
Background image of page 8
I t 0 τ τ 2 τ 3 τ 4 τ 0.37 I 0 I o / o ( ) t I t I e τ - = Current decreasing: Time Constant: R L =
Background image of page 9

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

View Full DocumentRight Arrow Icon
Example 2: Example 2: 12 V 200 mH 50k Ω 6 Ω I 3 I 2 I 1 a) The switch has been closed for a long time.
Background image of page 10
Background image of page 11

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

View Full DocumentRight Arrow Icon
Background image of page 12
Background image of page 13

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

View Full DocumentRight Arrow Icon
Background image of page 14
Background image of page 15
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Find the current through each component, and the voltage across each component. a) The switch is now opened. Find the currents and voltages just afterwards. Solution LC circuits LC circuits (Extra! – not on test/exam) (Extra! – not on test/exam) The switch is closed at t =0; Find I (t). C L I Which can be written as (remember, P=VI): +-Looking at the energy loss in each component of the circuit gives us: E L +E C =0 = + = + C Q dt dI L I C Q dt dI LI Solution RLC circuits RLC circuits (Extra! – not on test/exam) (Extra! – not on test/exam) The switch is closed at t =0; Find I (t). C L R I Which can be written as (remember, P=VI=I 2 R): +-Looking at the energy loss in each component of the circuit gives us: E L +E R +E C =0 2 = + + = + + C Q IR dt dI L I C Q R I dt dI LI Solution...
View Full Document

This note was uploaded on 03/16/2011 for the course PHYSIC 1e03 taught by Professor Dr.oak during the Spring '10 term at McMaster University.

Page1 / 15

lecture25 - Find the current through each component, and...

This preview shows document pages 1 - 15. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online