4.2 Electrical Quantities

Question 1

unit of measuring charge

Answer 1

coulombs (C)

Question 2

what is an electric field

Answer 2

the region in which another charge will experience a force

Question 3

direction of electrical field lines

Answer 3

positive charges- away

negative charges- towards

Question 4

conductor

Answer 4

material that allows charge to flow through it

Question 5

insulator

Answer 5

material that does not allow charge to flow through it

Question 6

electric current

Answer 6

flow of charge- can happen between two oppositely charged conductors connected by a wire

Question 7

current in terms of charge

Answer 7

charge per second

Question 8

formula for charge

Answer 8

Q = I x t 
charge = current x time

Question 9

unit of measuring current

Answer 9

ampes (A)

Question 10

device for measuring current

Answer 10

Ammeter

Question 11

cause of current

Answer 11

flow of electrons

Question 12

direction of flow of electrons

Answer 12

negative to positive

Question 13

direction of flow of current

Answer 13

positive to negative

Question 14

electromotive force (EMF)

Answer 14

Potential Difference (Voltage) of the
power source in a circuit

Question 15

unit for measuring EMF

Answer 15

volts (V)

Question 16

EMF in terms of energy

Answer 16

energy per coulomb (charge)

Question 17

potential difference

Answer 17

the amount of energy transferred by each unit of charge passing between those two points

Question 18

unit for measuring potential difference

Answer 18

Volts (V)

Question 19

relationship between energy and potential difference

Answer 19

1 Volt = 1 joule per coulomb

Question 20

device for measuring potential difference

Answer 20

Voltmeter (in parallel)

Question 21

resistance

Answer 21

opposition to current

Question 22

measuring unit of resistance

Answer 22

ohm (the sign that looks like a horse shoe)

Question 23

formula for resistance

Answer 23

potential difference/current

Question 24

to increase resistance

Answer 24

longer wire

Question 25

to decrease resistance

Answer 25

thicker wire (higher cross-sectional area)

Question 26

wire resistance and length relationship

Answer 26

directly proportional

Question 27

wire resistance and cross-sectional area relasionship

Answer 27

inversely proportional

Question 28

current and potential difference relationship

Answer 28

directly proportional

Question 29

factors effecting the amount of electrical energy used by a component

Answer 29

1- the current
2- the potential difference
3- amount of time the device is used for

Question 30

formula for energy transferred

Answer 30

E = I x V x t

= current x potential difference x time

Question 31

unit for energy

Answer 31

joules (J)

Question 32

electric power

Answer 32

energy per second

Question 33

formula for electric power

Answer 33

P = current x potential difference
P = I x V

Question 34

unit for power

Answer 34

watt (W) or joules per second (J/s)