This document provides information about electricity and related topics. It defines key terms like voltage, current, wattage, fuse usage, and wire colors in plugs. It describes circuit types like series and parallel and components like resistors, motors, and transformers. Safety around electricity for humans is also covered. Color mixing and telecommunications topics like satellites, optical fibers and their properties are summarized. Equations for electrical concepts are provided and thermometer types are defined.

1. ELECTRICITYELECTRICITY
Value ofValue of
mains supply =mains supply =
230V230V

2. ELECTRICITYELECTRICITY
Fuse is used as aFuse is used as a
safety devicesafety device
Prevents too muchPrevents too much
current flowing incurrent flowing in
circuit.circuit.

3. ELECTRICITYELECTRICITY
Power ofPower of
appliancesappliances
measured inmeasured in
watts (W)watts (W)

4. ELECTRICITYELECTRICITY
Plug wires – coloursPlug wires – colours
Live – brownLive – brown
Neutral – blueNeutral – blue
Earth – green/yellowEarth – green/yellow
Fuse in live position

5. ELECTRICITYELECTRICITY
Double insulation – no earthDouble insulation – no earth
wire required as casing ofwire required as casing of
appliance is plastic –nonappliance is plastic –non
conductorconductor

6. ELECTRICITYELECTRICITY
Human being is a conductorHuman being is a conductor
of electricity so do not touchof electricity so do not touch
wires ,do not come intowires ,do not come into
contact with water withcontact with water with
electricity.electricity.

7. ElectricityElectricity
PARTS OF THE RADIOPARTS OF THE RADIO
1. AERIAL - PICKS UP ALL1. AERIAL - PICKS UP ALL
SIGNALSSIGNALS
2. TUNER – SELECTS2. TUNER – SELECTS
ONE PARTICULARONE PARTICULAR
SIGNALSIGNAL

8. TELECOMTELECOM
3.3. DECODER –DECODER –
SEPARATES CARRIERSEPARATES CARRIER
WAVE FROM AUDIOWAVE FROM AUDIO
WAVEWAVE
4. AMPLIFIER – MAKES4. AMPLIFIER – MAKES
BIGGER COPY OF AUDIOBIGGER COPY OF AUDIO
WAVEWAVE

9. TELECOMTELECOM
5. BATTERY – SUPPLIES5. BATTERY – SUPPLIES
ENERGY TO AMPLIFIERENERGY TO AMPLIFIER
6. LOUDSPEAKER –6. LOUDSPEAKER –
CHANGES ELECTRICALCHANGES ELECTRICAL
ENERGY TO SOUNDENERGY TO SOUND
ENERGYENERGY

10. TELECOMTELECOM
COLOUR MIXINGCOLOUR MIXING
3 PRIMARY COLOURS –3 PRIMARY COLOURS –
RED , GREEN , BLUERED , GREEN , BLUE
TOGETHER MAKE WHITETOGETHER MAKE WHITE

11. TELECOMTELECOM
RED AND GREEN GIVERED AND GREEN GIVE
YELLOW.YELLOW.
RED AND BLUE GIVERED AND BLUE GIVE
MAGENTAMAGENTA
GREEN AND BLUE GIVEGREEN AND BLUE GIVE
CYANCYAN

12. TELECOMTELECOM
GEOSTATIONARYGEOSTATIONARY
SATELLITES ARE AT ASATELLITES ARE AT A
HEIGHT OF 36 , 000KmHEIGHT OF 36 , 000Km
ABOVE THE EARTHABOVE THE EARTH
THEY HAVE A 24 HRTHEY HAVE A 24 HR
ORBITORBIT

13. TELECOMTELECOM
SIGNALS ARESIGNALS ARE
MICROWAVE ANDMICROWAVE AND
TRAVEL IN A STRAIGHTTRAVEL IN A STRAIGHT
LINE TO AND FROM THELINE TO AND FROM THE
SATELLITE.THEYSATELLITE.THEY
CANNOT CURVE IN THECANNOT CURVE IN THE
EARTH`S ATMOSPHEREEARTH`S ATMOSPHERE

14. TELECOMTELECOM
OPTICAL FIBRES USEDOPTICAL FIBRES USED
TO CARRY INFORMATIONTO CARRY INFORMATION
BY TOTAL INTERNALBY TOTAL INTERNAL
REFLECTION. LIGHTREFLECTION. LIGHT
TRAVELS AT A SPEED OFTRAVELS AT A SPEED OF
200 , 000 , 000 M/S200 , 000 , 000 M/S

15. ELECTRICITYELECTRICITY
 EQUATIONSEQUATIONS
 Q = I x TQ = I x T V = I x RV = I x R
 P = I x VP = I x V P = E / tP = E / t
 P = VP = V22
/ R/ R P = IP = I22
RR
 RRTT = R= R11 + R+ R22
 1 /R1 /RTT = 1/R= 1/R11 + 1/R+ 1/R22

16. ELECTRICITYELECTRICITY
 RULES FOR SERIES AND PARALLELRULES FOR SERIES AND PARALLEL
CIRCUITSCIRCUITS
 VOLTAGE SPLITS UP IN A SERIES CIRCUITVOLTAGE SPLITS UP IN A SERIES CIRCUIT
 CURRENT STAYS THE SAME IN A SERIESCURRENT STAYS THE SAME IN A SERIES
CIRCUITCIRCUIT
 VOLTAGE STAYS THE SAME IN A PARALLELVOLTAGE STAYS THE SAME IN A PARALLEL
CIRCUITCIRCUIT
 CURRENT SPLITS UP IN A PARALLELCURRENT SPLITS UP IN A PARALLEL
CIRCUITCIRCUIT

17. ELECTRICITYELECTRICITY
 VOLTMETERS MEASURE VOLTAGEVOLTMETERS MEASURE VOLTAGE
AND GO ACROSS THE COMPONENTAND GO ACROSS THE COMPONENT
 AMMETERS MEASURE CURRENT ANDAMMETERS MEASURE CURRENT AND
ARE WIRED IN SERIES WITH THEARE WIRED IN SERIES WITH THE
COMPONENTS.COMPONENTS.
 CIRCUIT COMPONENTS INCLUDECIRCUIT COMPONENTS INCLUDE
RESISTORS , BULBS ETC.RESISTORS , BULBS ETC.

18. ELECTRICITYELECTRICITY
 MAINS ELECTRICITYMAINS ELECTRICITY
 WIRES IN THREE PIN PLUGWIRES IN THREE PIN PLUG
 1.1. BROWN LIVEBROWN LIVE 2. BLUE NEUTRAL2. BLUE NEUTRAL
 3. GREEN / YELLOW EARTH3. GREEN / YELLOW EARTH
 FUSE IS A SAFETY DEVICE WIRED IN THEFUSE IS A SAFETY DEVICE WIRED IN THE
 LIVE PINLIVE PIN
 EARTH WIRE NOT NEEDED FOR DOUBLEEARTH WIRE NOT NEEDED FOR DOUBLE
INSULATED APPLIANCES , THEY HAVE AINSULATED APPLIANCES , THEY HAVE A
PLASTIC CASINGPLASTIC CASING

19. ELECTRICITYELECTRICITY
 MAINS ELECTRICITYMAINS ELECTRICITY
 THREE TYPES OF CIRCUITTHREE TYPES OF CIRCUIT
 1. THE LIGHTING CIRCUIT 15A FUSE1. THE LIGHTING CIRCUIT 15A FUSE
2. THE RING MAINS CIRCUIT 30A2. THE RING MAINS CIRCUIT 30A
FUSEFUSE 3.3. THE COOKER CIRCUIT 45ATHE COOKER CIRCUIT 45A
FUSEFUSE
 ALL ARE WIRED IN PARALLEL IF ONEALL ARE WIRED IN PARALLEL IF ONE
GOES OUT THE OTHERS STAY ONGOES OUT THE OTHERS STAY ON
LESS WIRE USED SO MONEY ISLESS WIRE USED SO MONEY IS
SAVEDSAVED

20. ELECTRICITYELECTRICITY
 ELECTRIC MOTORSELECTRIC MOTORS
 COIL OF WIRE CARRYING CURRENTCOIL OF WIRE CARRYING CURRENT
SURROUNDED BY A PAIR OFSURROUNDED BY A PAIR OF
MAGNETSMAGNETS
 THE MORE TURNS ON THE COIL ANDTHE MORE TURNS ON THE COIL AND
THE STRONGER THE MAGNET , THETHE STRONGER THE MAGNET , THE
FASTER THE COIL GOES.FASTER THE COIL GOES.

21. ELECTRICITYELECTRICITY
 TWO COILS OF WIRE WITH AN IRONTWO COILS OF WIRE WITH AN IRON
CORE , THE PRIMARY COIL AND THECORE , THE PRIMARY COIL AND THE
SECONDARY COILSECONDARY COIL
 TRANSFORMERSTRANSFORMERS
 NNPP /N/NSS = V= VPP / V/ VSS
 IIPP x Vx VPP = I= ISS x Vx VSS

22. HEALTHHEALTH
 TYPES OF THERMOMETERTYPES OF THERMOMETER
 1. THE LAB THERMOMETER1. THE LAB THERMOMETER 2. THE2. THE
CLINICAL THERMOMETER BOTHCLINICAL THERMOMETER BOTH
LIQUID IN GLASS THERMOMETERSLIQUID IN GLASS THERMOMETERS 3.3.
THE DIGITAL THERMOMETERTHE DIGITAL THERMOMETER
 DIFFERENCE BETWEEN LAB ANDDIFFERENCE BETWEEN LAB AND
CLINICAL THERMOMETERS,CLINICAL THERMOMETERS,
SIZE,SCALE, MAGNIFIER IN CLINICALSIZE,SCALE, MAGNIFIER IN CLINICAL
THERMOMETER,KINKTHERMOMETER,KINK