chapter 18-19

Question 1

electric charge

Answer 1

a property of an object that allows it to be attached or repelled from another charged object

Question 2

static electricity

Answer 2

the buildup of electric charge on the surface of an object

Question 3

what is the charge of a proton

Answer 3

+ 1.6 x 10^-19 C

Question 4

what is the charge of an electron

Answer 4

-1.6 x 10^-19 C

Question 5

1 Coulomb of charge has ____ electrons

Answer 5

6.25 x 10^18

Question 6

electrically neutral

Answer 6

equal amounts of positive and negative charge

Question 7

conductors

Answer 7

objects that allow charges to move freely (ex: metals and salty water)

Question 8

insulators

Answer 8

objects that do not allow charges to move freely (ex: rubber and wood)

Question 9

semi-conductors

Answer 9

objects that act as both conductors and insulators depending on the temperature (ex; silicon and germanium)

Question 10

charges in a conductor will move to the ___ as they can move freely

Answer 10

the surface

Question 11

charges in an insulator will remain in ___

Answer 11

one place as they can’t move freely

Question 12

when objects are charged, electric charge is …

Answer 12

transferred between objects; the total amount of charge in the system doesn’t change during this process

Question 13

turboelectric charging

Answer 13

happens when two charged materials are rubbed against each other transferring charges from one material to the other. This leaves one material with a net positive charge and the other with a net negative charge

Question 14

charging by conduction

Answer 14

occurs when a charged conductor is placed in contact with a neutral conductor; charges evenly distributed throughout the two conductors

Question 15

charge by induction

Answer 15

this created a charge in a nearby object without direct contact. the charged object is never touching the object being charged by induction and there is no transfer of charged

Question 16

polarization

Answer 16

occurs when charge separate but the object remains neutral. through polarization neutral objects can become attracted to a charged object. The object being charged receives a charge opposite that used to charge it

Question 17

unit for electric field

Answer 17

N/C

Question 18

electrostatic force

Answer 18

the attraction or repulsion between charges

Question 19

five rules for electric field lines

Answer 19

1. They always point in the same direction as
   the electric field at every point
2. They start at positive charges or infinity
3. They end at negative charges or infinity
4. The closer the field lines are, the stronger
   the electric field
5. The number of lines that enter or exit a
   charge is proportional to the magnitude of the charge

Question 20

when an electric field is applied to a conductor…

Answer 20

the charges of the conductor move until the field is perpendicular to the surface leaving one side of the conductor positively charged, the other negatively charged. This also created a stronger electric field nearby the conductor and the polarization of charges inside the conductor creates an opposing electric field cancelling any electric field inside the conductor

Question 21

electric potential energy

Answer 21

the amount of work required to bring a positive test charge close to a negative charge

Question 22

electric potential

Answer 22

the potential energy per unit charge (unit is Volts)

Question 23

electric potential difference

Answer 23

occurs when there is a change in electric potential between two points; electric potential difference is also known as voltage

Question 24

electron-volt

Answer 24

the energy required to accelerate a fundamental charge through a voltage of one volt

Question 25

the electric potential decreases in the direction of…

Answer 25

the electric field and remains constant in the direction perpendicular to the electric field

Question 26

electric current

Answer 26

the rate at which charge flows. large currents move a lot of charge in a small amount of time where small current one a small amount of charge in a large amount of time

Question 27

conventional current travels from…

Answer 27

a higher or positive potential to a lower or negative potential

Question 28

we use conventional current to define…

Answer 28

the direction that current flows

Question 29

resistors

Answer 29

impede the flow of current by providing resistance

Question 30

resistance

Answer 30

the measure of how much a certain material impedes the flow of current

Question 31

Ohms Law

Answer 31

states that the current traveling in a wire is directly proportional to the voltage across the wire and inversely proportional to the resistance of the wire.

Question 32

Materials that follow Ohm’s Law are called…

Answer 32

Ohmic Materials and have a linear relationship between current, voltage, and resistance.

Question 33

Materials that do not follow Ohm’s Law are called…

Answer 33

Non-Ohmic Materials and have an exponential relationship between current, voltage, and resistance

Question 34

We use Ohm’s Law to determine…

Answer 34

the voltage drop across a resistor in a simple circuit.

Question 35

A simple circuit consists of…

Answer 35

a battery connected using wires to a resistor.

Question 36

power

Answer 36

the rate at which energy is used

Question 37

electrical power

Answer 37

the rate at which electric potential energy is supplied or dissipated

Question 38

direct current

Answer 38

describes the flow of electric charge in only one direction where voltage and current are always constant

Question 39

alternating current

Answer 39

describes the flow of oscillating charges that constantly change direction

Question 40

short circuits

Answer 40

occur when the path current takes is suddenly shortened, increasing the current to an unsafe amount that
increases the temperature of the wi

Question 41

short circuits

Answer 41

occur when the path current takes is suddenly shortened, increasing the current to an unsafe amount that
increases the temperature of the wire

Question 42

in an all inseries circuit…

Answer 42

the current is the same for all resistors

Question 43

in an all in parallel circuit…

Answer 43

the voltage is the same for all resistors