Electricity

Question 1

What is static electricity?

Answer 1

When insulating materials become electrically charged when rubbed together.
When they have the same charge, they repel causing static electricity

Question 2

What happens when material is rubbed together ? (4)

Answer 2

Negative electrons move from one material to the other

The material that loses electrons becomes positively charged

The material that gains electrons become negatively charged

Both materials gain equal amounts of opposite charge

Question 3

Why don’t you get static electricity from metals?

Answer 3

Static only works through insulating objects

Electrical charges move easily through conductors like metals

Question 4

What happens when the charges are the same?

Answer 4

Materials repel

Question 5

What happens when the charges are opposite

Answer 5

Material attract

Question 6

What happens when one material is charged and the other is not?

Answer 6

The materials attract

Question 7

What does a cell look like?

Answer 7

• | ▪️-

Question 8

What does a battery look like?

Answer 8

• |▪️•••|▪️-

Question 9

What does a diode look like?

Answer 9

A circle with a like through it with a triangle and another line in it going to opposite way

Question 10

What is the different in current between a series circuit and a parallel one?

Answer 10

Series= current is the same in every component

Parallel= current splits done the branches

Question 11

What is current ?

Answer 11

Measured in amps (I)

Flow of electrical charge

Question 12

When can’t current flow ?

Answer 12

If the switch is open

Question 13

How do you measure current?

Answer 13

Use an ammeter

Question 14

What is charge measured in

Answer 14

Measured in coulombs (C)

Question 15

What is voltage sometimes called?

Answer 15

Potential difference

Question 16

What is voltage measured in?

Answer 16

Volts

Question 17

How do you measure voltage ?

Answer 17

Use a voltmeter

Question 18

What happens to the potential difference when more cells are added?

Answer 18

The total potential difference is the sum of potential difference

E.g if 2 1.5 cells are added. The potential difference will be 3 V

Question 19

What happens to the current if more cells are added in a series circuit?

Answer 19

The current increases as more cells are added

Question 20

What is another word for cell?

Answer 20

Battery

Question 21

What is the relationship between voltage and current?

Answer 21

They are directly proportional

Question 22

What is resistance?

Answer 22

Measured it ohms (weird horseshoe sign)

Symbol is R

Question 23

What does resistance depend on?

Answer 23

Length of the wire

Thickness of the wire

Question 24

How does an electric current form?

Answer 24

Electrons move through a conductor colliding with ions

Question 25

What do ions cause?

Answer 25

Resistance

Question 26

What is the difference in resistance between a short wire and a long wire?

Answer 26

Resistance is greater in a long wire because electrons collide with ions more often

Question 27

What is the difference in resistance between a thin wire and a thick wire?

Answer 27

The resistance of a thin wire is greater because the thin wire had fewer electrons to carry the current

Question 28

What does a resister look like?

Answer 28

-[]-

Question 29

When are current and voltage not directly proportional

Answer 29

In a filament lamp

Question 30

What's the relationship between the temperature of a filament and the resistance of a lamp?

Answer 30

Directly proportional

Question 31

What are diodes?

Answer 31

Electronic components which regulate potential difference | It makes the resistance flow in the direction of current

Question 32

What are LED emitting diodes?

Answer 32

They produce light when current flows through It is used in computers They use smaller current

Question 33

What is a thermistor ?

Answer 33

Temperature sensor in fire alarms Low temperature - resistance is high - little current flows through High temperature - resistance is low- more current flows through

Question 34

What is LDR?

Answer 34

Used to detect light levels -security lights In the dark (low light levels) the resistance is high - little current In the light the resistance is low and more current can flow through

Question 35

What does ACDC stand for?

Answer 35

Direct current and alternating current

Question 36

What's alternating current

Answer 36

The direction of current changes many times per second | It has a frequency of 50 hz

Question 37

What is direct current ?

Answer 37

The current flows in one direction

Question 38

Advantage of direct current

Answer 38

Batteries produce low voltage dc so many devices can be portable

Question 39

Adv for alternating current

Answer 39

Reduces energy loss with transformers

Question 40

Features of a plug (5)

Answer 40

Case is made of rubber because it's a good insulter 3 pins made of brass because they are good conductors Fuse between live terminal and live pin Fuse breaks if there is too much current Cable is secured by cable grip

Question 41

How to wire a plug (3)

Answer 41

Blue (neutral) goes left Brown (live) goes right Striped (earth) flies to the top

Question 42

What is the period?

Answer 42

Time taken for one oscillation

Question 43

What is power measured in

Answer 43

Watts

Question 44

Which fuse is the best?

Answer 44

3A, 5A, 13 A 13A is usually the best