Lecture17 - Physics 132 Introductory Physics: Electricity...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
1 February 15, 2008 Physics 132-Winter 2008 Prof. Jim Beatty-Ohio State 1 Physics 132 Introductory Physics: Electricity and Magnetism Winter Quarter 2008 Lecture 17 February 15, 2008 Physics 132-Winter 2008 Prof. Jim Beatty-Ohio State 2 Capacitors, Resistors, and Power Key results so far: –Capacitors: Q=CV • Parallel: C eq = C 1 +C 2 • Series: 1/C eq = (1/C 1 + 1/C 2 ) –Resistors: V=IR • Power Dissipation: P = I 2 R =V 2 /R Let’s apply these to some 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
2 February 15, 2008 Physics 132-Winter 2008 Prof. Jim Beatty-Ohio State 3 Resistors in Series R 1 R 2 + E I Resistors in series carry the same current . Begin at negative battery terminal, clockwise: Across battery from - to +: + E Across R1 with current: -IR 1 Across R2 with current: -IR 2 Back to starting point: sum is zero + E - IR 1 - IR 2 = 0 E = I(R 1 + R 2 ) = I R tot R tot = R 1 + R 2 Resistors in series add like capacitors in parallel. February 15, 2008 Physics 132-Winter 2008 Prof. Jim Beatty-Ohio State 4 Multiloop Circuits and Kirchhoff’s Laws A step-by-step procedure allows us to understand even complicated multiloop circuits. Start at junctions (where wires meet) Label each branch with an I. (Directions are arbitrary, but you need to put them on the diagram!) At each junction, Σ I = 0 (Kirchhoff’s Current Law) For each closed loop, Σ V = 0 (Kirchhoff’s Voltage Law) You get one equation for each junction and for each closed loop. You should get enough equations to solve for all the unknowns. (Sometimes you get extra equations, which should lead to the same solutions.)
Background image of page 2
3 February 15, 2008 Physics 132-Winter 2008 Prof. Jim Beatty-Ohio State 5 Resistors in Parallel R eq + E Resistors in parallel have the same potential across them. Apply Kirchhoff’s Laws to find the
Background image of page 3

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

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/18/2008 for the course PHYS 132 taught by Professor Beatty during the Winter '08 term at Ohio State.

Page1 / 9

Lecture17 - Physics 132 Introductory Physics: Electricity...

This preview shows document pages 1 - 4. Sign up to view the full document.

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