ELECTRICITYELECTRICITY

Value of Value of mains supply mains supply = 230V= 230V

ELECTRICITYELECTRICITY

Fuse is used as a Fuse is used as a safety devicesafety device

Prevents too much Prevents too much current flowing in current flowing in

circuit.circuit.

ELECTRICITYELECTRICITY

Power of Power of appliances appliances

measured in measured in watts (W)watts (W)

ELECTRICITYELECTRICITY

Plug wires – coloursPlug wires – colours

Live – brownLive – brown

Neutral – blueNeutral – blue

Earth – green/yellowEarth – green/yellow

Fuse in live positionFuse in live position

ELECTRICITYELECTRICITY

Double insulation – no Double insulation – no earth wire required as earth wire required as casing of appliance is casing of appliance is plastic –non conductorplastic –non conductor

ELECTRICITYELECTRICITY

Human being is a Human being is a conductor of electricity conductor of electricity

so do not touch wires ,do so do not touch wires ,do not come into contact not come into contact

with water with with water with electricity.electricity.

ElectricityElectricity

PARTS OF THE RADIOPARTS OF THE RADIO1. AERIAL - PICKS UP ALL 1. AERIAL - PICKS UP ALL

SIGNALSSIGNALS2. TUNER – SELECTS ONE 2. TUNER – SELECTS ONE

PARTICULAR SIGNALPARTICULAR SIGNAL

TELECOMTELECOM

3.3. DECODER – DECODER – SEPARATES CARRIER SEPARATES CARRIER

WAVE FROM AUDIO WAVEWAVE FROM AUDIO WAVE4. AMPLIFIER – MAKES 4. AMPLIFIER – MAKES BIGGER COPY OF AUDIO BIGGER COPY OF AUDIO

WAVEWAVE

TELECOMTELECOM

5. BATTERY – SUPPLIES 5. BATTERY – SUPPLIES ENERGY TO AMPLIFIERENERGY TO AMPLIFIER6. LOUDSPEAKER – 6. LOUDSPEAKER – CHANGES ELECTRICAL CHANGES ELECTRICAL

ENERGY TO SOUND ENERGY TO SOUND ENERGYENERGY

TELECOMTELECOM

COLOUR MIXINGCOLOUR MIXING3 PRIMARY COLOURS – 3 PRIMARY COLOURS –

RED , GREEN , BLUE RED , GREEN , BLUE TOGETHER MAKE WHITETOGETHER MAKE WHITE

TELECOMTELECOM

RED AND GREEN GIVE RED AND GREEN GIVE YELLOW.YELLOW.

RED AND BLUE GIVE RED AND BLUE GIVE MAGENTAMAGENTA

GREEN AND BLUE GIVE GREEN AND BLUE GIVE CYANCYAN

TELECOMTELECOM

GEOSTATIONARY GEOSTATIONARY SATELLITES ARE AT A SATELLITES ARE AT A

HEIGHT OF 36 , 000Km HEIGHT OF 36 , 000Km ABOVE THE EARTHABOVE THE EARTH

THEY HAVE A 24 HR THEY HAVE A 24 HR ORBITORBIT

TELECOMTELECOM

SIGNALS ARE MICROWAVE SIGNALS ARE MICROWAVE AND TRAVEL IN A AND TRAVEL IN A STRAIGHT LINE TO AND STRAIGHT LINE TO AND FROM THE SATELLITE.THEY FROM THE SATELLITE.THEY CANNOT CURVE IN THE CANNOT CURVE IN THE EARTH`S ATMOSPHEREEARTH`S ATMOSPHERE

TELECOMTELECOM

OPTICAL FIBRES USED OPTICAL FIBRES USED TO CARRY INFORMATION TO CARRY INFORMATION

BY TOTAL INTERNAL BY TOTAL INTERNAL REFLECTION. LIGHT REFLECTION. LIGHT

TRAVELS AT A SPEED OF TRAVELS AT A SPEED OF 200 , 000 , 000 M/S200 , 000 , 000 M/S

ELECTRICITYELECTRICITY

EQUATIONSEQUATIONS

Q = I x TQ = I x TV = 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 = I22RR RRTT = R = R1 1 + R+ R22

1 /R1 /RTT = 1/R = 1/R11 + 1/R + 1/R22

ELECTRICITYELECTRICITY

RULES FOR SERIES AND PARALLEL RULES FOR SERIES AND PARALLEL CIRCUITSCIRCUITS

VOLTAGE SPLITS UP IN A SERIES CIRCUITVOLTAGE SPLITS UP IN A SERIES CIRCUIT CURRENT STAYS THE SAME IN A SERIES CURRENT STAYS THE SAME IN A SERIES

CIRCUITCIRCUIT VOLTAGE STAYS THE SAME IN A PARALLEL VOLTAGE STAYS THE SAME IN A PARALLEL

CIRCUITCIRCUIT CURRENT SPLITS UP IN A PARALLEL CURRENT SPLITS UP IN A PARALLEL

CIRCUITCIRCUIT

ELECTRICITYELECTRICITY

VOLTMETERS MEASURE VOLTAGE VOLTMETERS MEASURE VOLTAGE AND GO ACROSS THE COMPONENTAND GO ACROSS THE COMPONENT

AMMETERS MEASURE CURRENT AND AMMETERS MEASURE CURRENT AND ARE WIRED IN SERIES WITH THE ARE WIRED IN SERIES WITH THE

COMPONENTS.COMPONENTS. CIRCUIT COMPONENTS INCLUDE CIRCUIT COMPONENTS INCLUDE

RESISTORS , BULBS ETC.RESISTORS , BULBS ETC.

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 DOUBLE EARTH WIRE NOT NEEDED FOR DOUBLE INSULATED APPLIANCES , THEY HAVE A INSULATED APPLIANCES , THEY HAVE A

PLASTIC CASINGPLASTIC CASING

ELECTRICITYELECTRICITY

MAINS ELECTRICITYMAINS ELECTRICITY THREE TYPES OF CIRCUITTHREE TYPES OF CIRCUIT

1. THE LIGHTING CIRCUIT 15A FUSE1. THE LIGHTING CIRCUIT 15A FUSE 2. 2. THE RING MAINS CIRCUIT 30A FUSETHE RING MAINS CIRCUIT 30A FUSE 3.3. THE COOKER CIRCUIT 45A FUSETHE COOKER CIRCUIT 45A FUSE

ALL ARE WIRED IN PARALLEL IF ONE ALL ARE WIRED IN PARALLEL IF ONE GOES OUT THE OTHERS STAY ON GOES OUT THE OTHERS STAY ON

LESS WIRE USED SO MONEY IS SAVEDLESS WIRE USED SO MONEY IS SAVED

ELECTRICITYELECTRICITY

ELECTRIC MOTORSELECTRIC MOTORS COIL OF WIRE CARRYING CURRENT COIL OF WIRE CARRYING CURRENT

SURROUNDED BY A PAIR OF SURROUNDED BY A PAIR OF MAGNETSMAGNETS

THE MORE TURNS ON THE COIL AND THE MORE TURNS ON THE COIL AND THE STRONGER THE MAGNET , THE THE STRONGER THE MAGNET , THE

FASTER THE COIL GOES.FASTER THE COIL GOES.

ELECTRICITYELECTRICITY

TWO COILS OF WIRE WITH AN IRON TWO COILS OF WIRE WITH AN IRON CORE , THE PRIMARY COIL AND THE CORE , THE PRIMARY COIL AND THE

SECONDARY COILSECONDARY COIL TRANSFORMERSTRANSFORMERS NNPP /N /NSS = V = VPP / V / VSS

IIPP x V x VPP = I = ISS x V x VSS

HEALTHHEALTH

TYPES OF THERMOMETERTYPES OF THERMOMETER 1. THE LAB THERMOMETER1. THE LAB THERMOMETER 2. 2. THE CLINICAL THERMOMETER BOTH THE CLINICAL THERMOMETER BOTH

LIQUID IN GLASS THERMOMETERSLIQUID IN GLASS THERMOMETERS 3. 3. THE DIGITAL THERMOMETERTHE DIGITAL THERMOMETER

DIFFERENCE BETWEEN LAB AND DIFFERENCE BETWEEN LAB AND CLINICAL THERMOMETERS, CLINICAL THERMOMETERS,

SIZE,SCALE, MAGNIFIER IN CLINICAL SIZE,SCALE, MAGNIFIER IN CLINICAL THERMOMETER,KINKTHERMOMETER,KINK