1. Plan for Today (AP Physics I)
Go over Multiple Choice Questions/Review
Review for Test

2. Understand and be able to describe static electricity
Static electric about charge build up – excess or deficit of electrons
Can get charge separation in conductors
Conductors – allow electrons to move
Insulators – prevent electrons from moving
Can get charge by contact – causes like charges
Or charge by induction – causes opposite charges

3. Describe the following balloon demonstrations
Balloon on wall
Charge build up on balloon from rabbit’s fur, charge separation on wall so we have – balloon, + section of wall
Van de Graaff, can, and grounded sphere
Can has charge separation, attracted to Van de Graaff, then charge transfer, repelled from Van de Graaff and attracted to grounded sphere, charge transfer. . .
Packing peanuts in a conductor and insulator
No charge on inside of a conductor = nothing happens
Can get charges on inside of insulator because charges move there and stay

4. Also magic wand demonstration

5. Calculate the force on a charged particle

6. Calculate the electric field or the force from an electric field

7. Draw the electric field lines of one or more particles
Like we did earlier
Rules
Begin at +, end at –
Set scale
Never cross lines
Evenly distribute lines
Use at least 4 or 5
Have arrows on lines (to negative charges)

8. Problems Types Worksheet with 3 charges, finding the force on one
Drawing electric field lines for point charges (given a charge and a scale)
Calculate the force and direction on a charge given the electric field strength
Converting electrons and protons to Coulombs
Pendulum problem

9. Find the force and direction acting on the charge farthest left in the following diagram.

10. Draw an diagram of the electric field between two charges close to each other, one with a charge of C and the other with a charge of – C.

11. Find the electric field at point P.
If a C charge were placed there, what charge would act on the particle?

12. A charged particle is made up of 1. 2. 10^5 protons
A charged particle is made up of 1.2 * 10^5 protons. What is the charge in Coulombs?

13. A charged particle has a charge of -2. 5 nC
A charged particle has a charge of -2.5 nC. How many electrons make up the charge?

14. Two like charges are on either end of a pendulum so they reach equilibrium. The length of each side is .25 m. When at equilibrium, the string on the pendulum makes an angle of 12 degrees with the vertical. Find the charge of the two particles. Each particle has a mass of 3 g.

15. Two like charges are on either end of a pendulum so they reach equilibrium. The length of each side is .25 m. When at equilibrium, the string on the pendulum makes an angle of 12 degrees with the vertical. Find the charge of the two particles.

16. Find the force and direction acting on the charge farthest left in the following diagram.

17. Draw an diagram of the electric field between two charges close to each other, one with a charge of C and the other with a charge of – C.

18. Find the electric field at point P.
If a C charge were placed there, what charge would act on the particle?

19. A charged particle is made up of 1. 2. 10^5 protons
A charged particle is made up of 1.2 * 10^5 protons. What is the charge in Coulombs?

20. A charged particle has a charge of -2. 5 nC
A charged particle has a charge of -2.5 nC. How many electrons make up the charge?