BellworkBellwork

What parts of the atom have What parts of the atom have electric charge?electric charge?

The electron and protonThe electron and proton

Cartoon and Cartoon and Advertisement Advertisement ProjectProject2/5/142/5/14

PresentingPresentingThe PresenterThe Presenter: (Extra Credit) : (Extra Credit) Introduce yourselfIntroduce yourself Present your cartoon / advertisementPresent your cartoon / advertisement Explain how it relates to the physics Explain how it relates to the physics

topicstopicsThe AudienceThe Audience: (Your C.W. Assignment): (Your C.W. Assignment) Presenter’s namePresenter’s name As someone is presenting briefly As someone is presenting briefly

describe the cartoon / advertisement.describe the cartoon / advertisement. What topic did the cartoon / What topic did the cartoon /

advertisement cover?advertisement cover?

AssignmentsAssignments

Cartoon, advertisement and Cartoon, advertisement and descriptions together in the descriptions together in the cabinetcabinet

Pass the class-work Pass the class-work assignment forwardassignment forward

Electric Force and Electric Force and Electric Field LinesElectric Field Lines

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Electric ForceElectric Force

Electric force is an action at a distance Electric force is an action at a distance forceforce

Can be attractive or repulsiveCan be attractive or repulsiveDifferent from gravity, which is an Different from gravity, which is an

attractive force.attractive force.

Electric Field LinesElectric Field Lines

Electric Field LinesElectric Field Lines: A way to represent : A way to represent the electric field around chargesthe electric field around charges

New QuantitiesNew QuantitiesChargeCharge (scalar): (scalar):

variable (equations): qunit (measured in): coulombs (C)

Electric ForceElectric Force (vector): (vector):

Variable: Felec

Unit: newton (N)Electric FieldElectric Field (vector): (vector):

Variable: Efield

Unit: newtons per coulomb (N/C)

Electrostatics Notes and Homework Assignment

• Read pages 500-514 and outline in your notes, there will questions about the information on a future Pop Quiz.

• Answer questions #1-25, in complete sentences, on page 515-516 to be turned in. (Due on Fri. 2/7/14)

Bellwork (2/7/14)Bellwork (2/7/14)

Turn in Electrostatic questions #1-25Turn in Electrostatic questions #1-25What is Mr. Z.’s favorite YouTube video What is Mr. Z.’s favorite YouTube video

of 2013?of 2013?

CalendarCalendar

Today – Electric Field LinesToday – Electric Field LinesMon. 2/10 – E-Field Lab dueMon. 2/10 – E-Field Lab dueTues. 2/11 – E-Field H.W. dueTues. 2/11 – E-Field H.W. due

Electric Field LinesElectric Field Lines

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Electric Field LinesElectric Field Lines1.1. Lines start on positive charges and end on Lines start on positive charges and end on

negative chargesnegative charges2.2. Label the chargesLabel the charges3.3. The number of lines represents the The number of lines represents the

magnitude of the charge magnitude of the charge (1 charge = 4 lines)4.4. Field lines cannot cross each otherField lines cannot cross each other5.5. Field lines must start or end on charges or Field lines must start or end on charges or

extend out to or from infinityextend out to or from infinity6.6. Field lines should show the electric field Field lines should show the electric field

between the charges evenlybetween the charges evenly7.7. Density of field lines represents the electric Density of field lines represents the electric

field strengthfield strength

Examples

Example #1: Two charges where one is +3q and the other is -3q

Example #2: Two charges where one is -2q and the other is -3q