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Flashcards in Physics Deck (192)
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1

How does an insulator become charged?

Electrons are transferred from one material to another by friction

2

What is charging caused by?

A loss or gain of electrons

3

What is important to remember about like charges?

They will repel

4

What is important to remember about unlike charges?

They attract

5

What happens when an appliance short circuits?

The live wire of an appliance touches the neutral wire

6

What is an earth wire used for?

If there is a fault in the circuit, the earth wire carries the charge into the ground

7

Circuit symbol for a cell

A longer vertical line parallel to a shorter parallel line on the right

8

Circuit symbol for a battery

Multiple cells joined together

9

Circuit symbol for lamp

Circle with a cross inside

10

Circuit symbol for a resistor

A clear rectangle

11

Circuit symbol for variable resistor

A rectangle with a diagonal arrow pointing from bottom left to top right

12

Circuit symbol for ammeter

Circle with an A inside

13

Circuit symbol for voltmeter

Circle with a V inside

14

Circuit symbol for switch

Two circles connected by a straight line

15

Circuit symbol for diode

A circle with a triangle and straight line inside

16

What is the difference between direct and alternating current?

An alternating current repeatedly reverses direction

17

What is the difference between conductors and insulators?

A conductor allows energy to pass through it whereas an insulator doesn't

18

Examples of conductors

Copper and aluminium

19

Examples of insulators

Plastics and rubber

20

Equation for current

Charge flow / time

21

What are voltmeters used for?

Measures the potential difference across a component

22

Equation for resistance

Potential difference / current

23

What does the V-I graph for a fixed resistor look like?

A diagonal line from bottom left to top right directly through the origin

24

What does the V-I graph for a filament lamp look like?

A curve from bottom left to top right passing directly through the origin

25

Properties of LDRs

Resistance decreases with light intensity

26

Properties of ideal diodes

Allows the current to flow in one direction only

27

What are the rules for current in a series circuit?

The same current passes through each component

28

What are the rules for voltage in a series circuit?

The total potential difference is shared between the components

29

How to calculate the total resistance in a series circuit?

Add the resistances of each component

30

What are the rules for current in a parallel circuit?

The total current is the sum of the currents passing through the branches