ELECTRICITY

Question 1

WHATS AN ELECTRIC CURRENT?

Answer 1

Flow of electrical charge

Question 2

WHAT IS AN ELECTRICAL CHARGE?

Answer 2

Only flows through a closed circuit if there’s a potential difference

Question 3

WHAT IS A SINGLE CLOSED LOOP?

Answer 3

Same value everywhere in the circuit

Question 4

WHAT DOES POTENTIAL DIFFERENCE DO?

Answer 4

Pushes charge round

The unit is volts

Question 5

WHAT IS RESISTANCE?

Answer 5

Slows the flow down

Unit is Ohms

Question 6

WHAT DOES THE CURRENT DEPEND ON

Answer 6

The potential difference and resistance

Question 7

THE GREATER THE RESISTANCE…

Answer 7

The small the current flows

Question 8

WHAT IS CURRENT?

Answer 8

Rate of the flow of the charge

Question 9

WHAT IS THE EQUATION FOR MEASURING THE CHARGE FLOW

Answer 9

Q=IT

Question 10

WHAT IS THE SYMBOL FOR AN LED

Answer 10

V

Question 11

WHAT IS THIS SYMBOL?

Answer 11

A variable resistor

Question 12

IS THIS THE SYMBOL FOR A FUSE, THERMISTOR OR RESISTOR?

Answer 12

Thermostat

Question 13

WHICH OF THESE SYMBOLS IS A DIODE, LDR AND LED?

Answer 13

H

Question 14

WHAT IS THE EQUATION FOR WORKING OUT THE POTENTIAL DIFFERENCE?

Answer 14

V=IR

Question 15

WHAT DOES THE RESISTANCE OF A CIRCUIT DEPEND ON

Answer 15

Many factors like the type of circuit, length of the wire, etc

Question 16

WHAT DOES AN AMMETER DO?

Answer 16

Measure the current flowing through the test wire in amps

Question 17

WHAT SOES A VOLT METER DO?

Answer 17

Measures the potential difference across the wire

Question 18

WHERE IS THE AMMETER PLACES IN A CIRCUIT?

Answer 18

In series with whatever you’re investigating

Question 19

WHERE IS A VOLTMETER PLACED IN A CIRCUIT?

Answer 19

Placed in parallel to whatever you’re investigating

Question 20

WHAT IS RESISTANCE?

Answer 20

Anything in the circuit which reduces the flow of the current

Question 21

WHAT DETERMINES THE CURRENT FLOWING THROUGH A CURRENT?

Answer 21

Resistance of and potential difference across a component

Question 22

WHAT DOES AN OHMIC CONDUCTOR HAVE?

Answer 22

A constant resistance eg wire

Question 23

WHEN IS THE CURRENT FLOWING THEOUGH AN OUMIC CONDUCTOR PROPORTIONAL TO THE POTENTIAL DIFFERENCE ACROSS IT?

Answer 23

At a constant temperature

Question 24

WHAT DOES IT MEAN WHEN COMPONENTS ARENT OHMNIC?

Answer 24

Their resistance changes with the current through them, eg diodes and lamps

Question 25

WHAT IS AN I-V CHARACTERISTIC?

Answer 25

How the current varies as you change the potential difference across a component

Question 26

WHAT I-V CHARACTERISTICS HAS LINEAR COMPONENTS?

Answer 26

OHMNIC conductors as the resistance stays the same

Question 27

WHY DOES A NON LINEAR COMPONENT HAVE A CURVED I-V CHARACTERISTIC?

Answer 27

The resistance changes depending on the current

Question 28

WHAT IS A FILAMENT LAMP?

Answer 28

It transfers some energy into thermal

Question 29

WHEN DOESNR RESISTANCE INCREASE WITH A FILAMENT LAMP?

Answer 29

It increases with the temperature as more current flows, the resistance increases

Question 30

WHERE DOES THE CURRENT FLOW THROUGH A DIODE

Answer 30

In one direction

Question 31

WHAT DOES RESISTANCE DEPEND ON WITH A DIODE?

Answer 31

The direction of the current

Question 32

WHAT DOES A GRAPH LOOK LIKE WITH A FIXÉD RESISTOR?

Answer 32

Gsjfvv

Question 33

WHAT DOES A GRAPH LOOK LIKE WITH A FILAMENT LAMP?

Answer 33

Dbevcvev

Question 34

WHAT DOES A GRAPH LOOK LIKE WITH A DIODE?

Answer 34

Shdvgdh

Question 35

WHAT IS LDR?

Answer 35

Light Dependent Resistor that detects light levels Rosi stances decreases—> light intensity increases

Question 36

WHAT IS LED?

Answer 36

It’s a diode that glows when electricity passes in one direction

Question 37

WHAT DOES THIS DISGRAM DO?

Answer 37

Turns on when dark Used in street lamps, flash on camera, brightness on screens, etc

Question 38

WHAT DOES THIS DIAMGRAM DO?

Answer 38

Turns on when there’s light

Question 39

WHATS A THERMISTOR?

Answer 39

It’s like LDR but works with heat Used in central heating

Question 40

LABEL HIS DIAGRAM?

Answer 40

``` A earth wire B outer flexible insulation C live fuse wire D cord grip E Neutral wire ```

Question 41

WHATS A FUSE?

Answer 41

Melts when a currents too high

Question 42

WHAT ARE THE TYPES OF FUSES?

Answer 42

1A, 3A,5A,13A

Question 43

WHAT ARE CURRENT BREAKERS?

Answer 43

Electronic fuses that reset easily

Question 44

WHAT DOES RCCB STAND FOR?

Answer 44

Residual Current Breakers

Question 45

WHAT DOES AN RCCB DO?

Answer 45

Ministers current in live and neutral wires If there’s a difference it cuts the current immediately preventing electricution

Question 46

WHAT IS THE NATIONAL GRID

Answer 46

Network of cable & transformers that convert power stations to home & factories

Question 47

WHY IS ELECTRICITY IS TRANSMITTED AT A VERY HIGH VOLTAGE BY THE NATIONAL GRID?

Answer 47

To minimise energy lost