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SPEED
OF E .M .WAVES
3x 3oo,ooo,ooo m/s
8m/s 10
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SPEED
OF SOUND WAVES
340
m/s in air
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EQUATIONS
v=
fl
v = d /t
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= the number of waves per second Measured in Hertz (HZ)
Frequency
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WAVE –THIS TELLS YOU THE RADIO STATION AUDIO WAVE TELLS YOU WHAT IS ON THE STATION
CARRIER
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MODULATED (AM) WAVE –A COMBINATION OF THE CARRIER AND AUDIO WAVE
AMPLITUDE
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OF THE RADIO 1. AERIAL - PICKS UP ALL SIGNALS 2. TUNER – SELECTS ONE PARTICULAR SIGNAL
PARTS
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3.
DECODER – SEPARATES CARRIER WAVE FROM AUDIO WAVE 4. AMPLIFIER – MAKES BIGGER COPY OF AUDIO WAVE
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5.
BATTERY – SUPPLIES ENERGY TO AMPLIFIER 6. LOUDSPEAKER – CHANGES ELECTRICAL ENERGY TO SOUND ENERGY
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MIXING 3 PRIMARY COLOURS – RED , GREEN , BLUE TOGETHER MAKE WHITE
COLOUR
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AND GREEN GIVE YELLOW. RED AND BLUE GIVE MAGENTA GREEN AND BLUE GIVE CYAN
RED
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SATELLITES ARE AT A HEIGHT OF 36 , 000Km ABOVE THE EARTH THEY HAVE A 24 HR ORBIT
GEOSTATIONARY
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SIGNALS
ARE MICROWAVE AND TRAVEL IN A STRAIGHT LINE TO AND FROM THE SATELLITE.THEY CANNOT CURVE IN THE EARTH`S ATMOSPHERE
TELECOM
OPTICAL
FIBRES USED TO CARRY INFORMATION BY TOTAL INTERNAL REFLECTION. LIGHT TRAVELS AT A SPEED OF 200 , 000 , 000 M/S
ELECTRICITY
EQUATIONS
Q=IxT V=IxR P=IxV P=E/t P = V2 / R P = I2R RT = R1 + R2 1 /RT = 1/R1 + 1/R2
ELECTRICITY
RULES FOR SERIES AND PARALLEL CIRCUITS VOLTAGE SPLITS UP IN A SERIES CIRCUIT CURRENT STAYS THE SAME IN A SERIES CIRCUIT VOLTAGE STAYS THE SAME IN A PARALLEL CIRCUIT CURRENT SPLITS UP IN A PARALLEL CIRCUIT
ELECTRICITY
VOLTMETERS MEASURE VOLTAGE AND GO ACROSS THE COMPONENT AMMETERS MEASURE CURRENT AND ARE WIRED IN SERIES WITH THE COMPONENTS. CIRCUIT COMPONENTS INCLUDE RESISTORS , BULBS ETC.
ELECTRICITY
MAINS ELECTRICITY WIRES IN THREE PIN PLUG 1. BROWN LIVE 2. BLUE NEUTRAL 3. GREEN / YELLOW EARTH FUSE IS A SAFETY DEVICE WIRED IN THE LIVE PIN EARTH WIRE NOT NEEDED FOR DOUBLE INSULATED APPLIANCES , THEY HAVE A PLASTIC CASING
ELECTRICITY
MAINS ELECTRICITY THREE TYPES OF CIRCUIT 1. THE LIGHTING CIRCUIT 15A FUSE 2. THE RING MAINS CIRCUIT 30A FUSE 3. THE COOKER CIRCUIT 45A FUSE ALL ARE WIRED IN PARALLEL IF ONE GOES OUT THE OTHERS STAY ON LESS WIRE USED SO MONEY IS SAVED
ELECTRICITY
ELECTRIC MOTORS COIL OF WIRE CARRYING CURRENT SURROUNDED BY A PAIR OF MAGNETS THE MORE TURNS ON THE COIL AND THE STRONGER THE MAGNET , THE FASTER THE COIL GOES.
ELECTRICITY
TWO COILS OF WIRE WITH AN IRON CORE , THE PRIMARY COIL AND THE SECONDARY COIL TRANSFORMERS NP /NS = VP / VS IP x VP = IS x VS
HEALTH
TYPES OF THERMOMETER 1. THE LAB THERMOMETER 2. THE CLINICAL THERMOMETER BOTH LIQUID IN GLASS THERMOMETERS 3. THE DIGITAL THERMOMETER DIFFERENCE BETWEEN LAB AND CLINICAL THERMOMETERS, SIZE,SCALE, MAGNIFIER IN CLINICAL THERMOMETER,KINK