electricity

Question 1

What is the current

Answer 1

flow of charged particles through an electrical conductor

Question 2

how is the current represented

Answer 2

amperes(A)

Question 3

how is the current measured?

Answer 3

using an ammeter

Question 4

what is the potential difference

Answer 4

the work done to move charge between two points

Question 5

how is the p.d. represented

Answer 5

V

Question 6

What is the equation to represent the relationship between energy,charge, p.d

Answer 6

E=QxV

Question 7

what is to energise, charge VO!

Answer 7

energy= charge x p.d

Question 8

how is potential difference measured

Answer 8

voltmeter

Question 9

what is the resistance

Answer 9

opposition of the flow of current through a conductor

Question 10

how is resistance represented

Answer 10

Question 11

resist virtual intelligence

Answer 11

R=V/I

Question 12

what is a voltage current graph

Answer 12

displays the relationship between V and A

Question 13

what is an ohmic conductor

Answer 13

a fixed resistor that maintains constant resistance

Question 14

what is a non-ohmic conductor

Answer 14

not constant and produce a sigmoidal curve

Question 15

explain this graph

Answer 15

as more current flows through a filament lamp
it heats up due to the increase electron collisions
this heat leads to an increased resistance as the particles vibrate with more energy
making it harder for free electrons to flow through
decrease in current

Question 16

what are thermistors

Answer 16

components whose resistance is dependent on temperature

Question 17

explain this graph

Answer 17

as the temperature increases, resistance decreases

Question 18

what is a light dependent resistor(LDR)

Answer 18

components whose resistance is dependent on the light intensity

Question 19

explain this graph

Answer 19

resistance of ldr decreases as light intensity decreases

Question 20

what is an ideal diode

Answer 20

components that allow current to flow in one direction

Question 21

what are the practical characteristics of ideal diodes

Answer 21

require a forward junction potential before current flows through it
have a break down voltage in the reserve direction causing negative current

Question 22

what is the ideal characteristics graph of a diode

Answer 22

Question 23

what is the practical characteristics of a diode

Answer 23

Question 24

what’s a series circuit

Answer 24

current is the same in every component

Question 25

what is the p.d in series

Answer 25

the sum of all the p.d components

Question 26

what is the resistance in series

Answer 26

sum of all the components

Question 27

what is a parallel circuit

Answer 27

where the components have branches

Question 28

what is the p.d in parallel

Answer 28

the same to the overall p.d

Question 29

what is the current in parallel

Answer 29

sum of all the branches to overall

Question 30

what is reciprocal law

Answer 30

Question 31

what is power

Answer 31

the rate of work done

Question 32

energise, personal trainer

Answer 32

E= p x t

Question 33

how can transfer of electrical power be measured

Answer 33

p = v x I

Question 34

relationship between power, current and resistance

Answer 34

P= i2 xR

Question 35

what is a transformer

Answer 35

devices that have the ability to alter V and A

Question 36

what is a step-up transformer

Answer 36

increase voltage and decreases current

Question 37

what is a step-up transformer useful for

Answer 37

transfer of electricity from power stations to national grid to reduce energy loss

Question 38

what is a step down transformer

Answer 38

to decrease voltage and increase current

Question 39

what is a step down transformer useful for

Answer 39

to use in homes to reduce risk of electric shocks

Question 40

what does a transformer consist of

Answer 40

primary coil wrapped around a core

Question 41

what happens in this transformer

Answer 41

current flows through the primary coil creates a magnetic current which induces secondary coil A and V can be altered by varying the ratio of turns in the coils

Question 42

equations for transformers

Answer 42

power = primary voltage x primary current power = secondary voltage x secondary current

Question 43

what is the generator effect

Answer 43

generation of a current by the movement of an electrical conductor relative to a magnetic field

Question 44

what does a generator consist of

Answer 44

wire rotating in a magnetic field

Question 45

what happens as the wire rotates through a magnetic field

Answer 45

each side of the coil moves through the field in two different direction with each 360 rotation, producing ac

Question 46

what is a waveform

Answer 46

current changing direction at a certain regular frequency

Question 47

what is the frequency and voltage in the uk

Answer 47

50 Hz and 230 V

Question 48

what is an electrostatic conductor

Answer 48

material that is able to disperse electrons easily

Question 49

what is an electrostatic insulator

Answer 49

doesn’t disperse electrons easily

Question 50

what happens when insulators are rubbed together

Answer 50

flow of charge from one to other loss of electrons is positive gain is negative

Question 51

what happens to objects with the same charge

Answer 51

they repel each other if opposite charge they attract