Units
Formulas/Conventions
Capacitors
Extra practice problems
100

Units of Energy

Joules

100

formula for V and PE

V = kq/r, PE = qv

100

What is a capacitor

Device that stores charge

100

Problem 2

-0.77 J

200

Units of Charge

Coulombs

200

A positive particle is placed near stationary charge.  If electric potential is positive, is stationary charge positive or negative?

positive 

200

Negative charge is shot between + and negative places of  a capacitor, draw its path.  What controls how much it bends?

amount of charge

200

Extra practice problem 4

1.3 x 10^3 m/sec

300

Units of potential, v, delta v

volts

300

A freely moving particle is placed near a stationary negative charge.  If the freely-moving particle's potential energy is negative, is its charge positive or negative?

positive (V = k q / r where q is stationery, PE = qv where q is moving particle)

300

Extra practice problem 8

1.01 x 10^8 F

300

Extra practice problem 5

7.9 x 10^5 m/s

400

Units of capacitance, C

farads

400

A negative charge moves towards a negative charge.  As the two charges get closer, does potential energy increase or decrease?

increase
400

extra practice problem 9

1.8 x 10^7 m/sec

400

Extra practice problem 6

2.2 m

500

units of k

N m^2/C^2

500

When charge moves from negative potential to positive potential, is the change in potential + or negative

+

500

Extra practice problem 10

5.0 x 10^5 C

500

Extra practice problem 7

3.5 m