Electricity

Question 1

what is electricity

Answer 1

energy caused by the flow of electric charges

Question 2

what allows electricity to flow in metals

Answer 2

free moving electrons

Question 3

what can electrical energy be converted into

Answer 3

other forms of energy

Question 4

what is an electric circuit

Answer 4

path for electric charges to flow

Question 5

what are electrical conductors

Answer 5

materials that allow electricity to pass through easily

Question 6

what are electrical insulators

Answer 6

materials that do not allow electricity to pass through

Question 7

what is a short circuit

Answer 7

current flows through a low resistance path bypassing components

Question 8

what can a short circuit cause

Answer 8

very large current and possible fire

Question 9

what is electric current

Answer 9

rate at which electric charge flows

Question 10

what is the si unit of current

Answer 10

ampere

Question 11

what is conventional current

Answer 11

flow from positive to negative terminal

Question 12

what is electron flow

Answer 12

flow from negative to positive terminal

Question 13

what measures current

Answer 13

ammeter

Question 14

how should an ammeter be connected

Answer 14

in series with the circuit

Question 15

what is potential difference

Answer 15

energy needed to move a unit charge between two points

Question 16

what is the si unit of potential difference

Answer 16

volt

Question 17

what measures potential difference

Answer 17

voltmeter

Question 18

how is a voltmeter connected

Answer 18

across the component

Question 19

what is resistance

Answer 19

measure of how much a component opposes current flow

Question 20

what is the formula for resistance

Answer 20

potential difference divided by current

Question 21

what is the si unit of resistance

Answer 21

ohm

Question 22

what increases resistance in a wire

Answer 22

smaller cross-sectional area and longer length

Question 23

what device allows varying resistance

Answer 23

variable resistor

Question 24

what can variable resistors control

Answer 24

sound volume brightness and speed

Question 25

what is a sliding rheostat

Answer 25

resistor with adjustable length of resistive path

Question 26

how to connect a sliding rheostat

Answer 26

use one top and one bottom connection point

Question 27

what happens when slider moves right

Answer 27

resistance increases

Question 28

how many paths in a series circuit

Answer 28

one single path

Question 29

how is current in a series circuit

Answer 29

same throughout all components

Question 30

how is voltage distributed in series

Answer 30

total voltage equals sum of voltages across components

Question 31

how is resistance calculated in series

Answer 31

sum of all resistances

Question 32

how many paths in a parallel circuit

Answer 32

multiple branches

Question 33

how is current distributed in parallel

Answer 33

total current equals sum of currents in each branch

Question 34

what happens if a component breaks in parallel

Answer 34

others still work

Question 35

how is voltage in parallel

Answer 35

same across all branches

Question 36

how does resistance change in parallel

Answer 36

decreases as more resistors are added

Question 37

what causes heating effect

Answer 37

electric charges losing energy to particles in wire

Question 38

what is nichrome used for

Answer 38

heating appliances due to high resistance

Question 39

what causes lighting effect

Answer 39

filament heats up and glows due to current

Question 40

what shows magnetic effect of current

Answer 40

compass needle deflects near a current-carrying wire

Question 41

how to increase magnetic effect

Answer 41

increase coil turns current or add soft iron core

Question 42

what is an electromagnet

Answer 42

coil wound around soft iron core

Question 43

what is electrolysis used for

Answer 43

breaking down compounds using electricity

Question 44

what is electroplating

Answer 44

depositing metal layer using electrolysis

Question 45

how are batteries charged

Answer 45

electrical energy is converted to chemical energy

Question 46

how is stored energy used in batteries

Answer 46

converted back to electrical energy

Question 47

what is power

Answer 47

rate of energy transfer or conversion

Question 48

what is the formula for power

Answer 48

energy divided by time

Question 49

what is the si unit of power

Answer 49

watt

Question 50

how is electrical energy calculated

Answer 50

power multiplied by time

Question 51

what units are used for large appliances

Answer 51

kilowatts and kilowatt hours

Question 52

why are led bulbs preferred

Answer 52

more energy efficient with less wasted heat

Question 53

what causes electrical fires

Answer 53

large currents due to damaged or overloaded circuits

Question 54

what causes electric shocks

Answer 54

large current passing through body

Question 55

how to prevent electrical hazards

Answer 55

unplug before cleaning keep dry call electrician avoid overloading

Question 56

what is a fuse

Answer 56

safety device that melts with excessive current

Question 57

how does a fuse work

Answer 57

wire melts and breaks the circuit

Question 58

where is a fuse found

Answer 58

in three pin plugs

Question 59

what happens after a fuse blows

Answer 59

it must be replaced

Question 60

what is a circuit breaker

Answer 60

device that trips when current is too large

Question 61

how does a circuit breaker work

Answer 61

switch trips and cuts off current flow

Question 62

where is a circuit breaker found

Answer 62

in the consumer unit

Question 63

why are circuit breakers useful

Answer 63

prevent shocks and fires and do not need replacing