1. Electric Force and Fields

2. Electric Force
Definition: force of attraction or repulsion between charged particles
Depends on: distance and amount of charge
Who measured it: Charles Coulomb

3. Cheerios on Van De Graff
Draw a picture of the cheerio demonstration. What happens and why?
If the Van de Graff was negatively charged, what would happen if a negatively charged object was placed near it?
Draw the force on the objects due to the generator
Is the force stronger closer to the generator or father away? How do you know?

4. What would cause the electric force to become stronger?
Think back to what electric force depends on…
distance and amount of charge
Decrease distance and increase charge

5. Electric Field
Definition: area around a charged object in which other objects experience a force
What does it show? Direction a positive charge would move
What’s wrong with that? PROTONS DO NOT MOVE!!!

6. A few rules when drawing field lines
Lines should never cross each other
Number of lines indicate strength. The more lines, the greater the charge
Why use field lines? It predicts movement of charged particles

7. 1 positive object

8. 1 negative object

9. Two positive charges
Show the repulsion!!!

10. One positive and one negative
Show the attraction!!!

11. +2 charge and -1 charge
Note how many lines are coming out of the +2 charge and how many lines are coming into the -1 charge.