1. Electrostatics

2. Electrostatics Fe >> Fg Electrostatic Force (Fe)
- Study of electricity at rest
Electrostatic Force (Fe)
Attractive OR Repulsive
Fe = centripetal force keeping e- in orbit
Opposite Charges Attract
Like Charges Repel
Fe >> Fg
99% empty space
Electrons – loosely bound
Conductors - allow electrons to flow freely (Low e- affinity)
Protons & Neutrons – tightly bound in nucleus
Nucleus –
99% of atoms mass
Gold Atom - few valence electrons loosely bound

3. Insulators - do NOT allow electrons to flow freely
(High e- affinity)

4. Electrostatics -
Atomic Structure
Conductors Insulators

5. Detecting Charge: Charge Detecting Devices RULES
Describe Rutherfords findings in his famous Gold Foil Experiment.

6. 3 Methods of Charging Separation of Charge Charging by Contact
Friction Conduction Induction by Grounding
Outcome Outcome Outcome

7. Units of Charge: Negative Charge Positive Charge
Elementary Particles (e) => Coulombs (C)
What is the charge in Coulombs for...
a) -6e
b) +3e
Coulombs (C) => Elementary Particles (e)
How many extra/fewer e- does object have with charge of...
a) -3.2 X10-19C
b) 2.0 X10-19C
ELECTRON CANNOT BE CUT INTO PIECES!!

8. Conservation of Charge & Charge Transfer:
2 metal spheres touch then separate… A B
What is the charge on each sphere after contact?
What subatomic particle(s) were transferred? From where to where?
c) How much charge did A gain in elementary particles and Coulombs?
d) How much charge did B lose in elementary particles and Coulombs?
+4e
BEFORE
-6e
Total Charge =
What if? A B
AFTER
Total Charge =

9. Multistep Charge Transfer
MicroCoulomb (μC) :
a) How many elementary particles? b) How many MicroCoulombs?
-5 μC x 1012e
Analogy: 325cents. How many Quarters?
Analogy: 636eggs. How many dozen?
Multistep Charge Transfer
Two spheres have charges of +3µC and +7µC respectively...
What is the charge on each sphere after contact?
How much charge was transferred in.. µC C e q 1.
Net Charge =
Δq= Δq= 2.
Net Charge = 3.
Net Charge =

10. Two 1kg charged objects with charges of +2C and -4C are .5m apart…
Coulombs Law:
Two 1kg charged objects with charges of +2C and -4C are .5m apart…
What is the electrostatic force (Fe) between the objects?
What would be force if charges were +2C and +4C?
c) What is the gravitational force (Fg) between the objects?
Inverse Square Law Relationships
a) 4r
b) 2q1
c) 2q1, 3q2
d) 3q1, 3q2, 3r Fe Fe Fe Fe

11. Electric Field - E-Field Intensity/Strength
Electric Field Lines
E-Field vs. G-Field
Direction:
Rules:
What is the electric field strength if a point charge of 2C feels an attractive force of 10N?
Given the field strength in part ‘a’, how much force would a proton feels in this field?
If the sphere and the point charge are .1m apart, what must be the charge on the sphere?