Units, Prefixes and Scientific Notation



National 4/5PhysicsGleniffer High SchoolWAVESClass NotesContentsUnits, Prefixes and Scientific NotationSI unitsPrefixes and Scientific NotationScientific Notation PracticeConverting NumbersWave PropertiesTransverse and Longitudinal WavesWave CharacteristicsWave SpeedFrequencyPeriodThe Wave EquationWave Properties SummaryDiffractionDiffractionSoundThe Speed of SoundWaveformsNoise and DecibelsUltrasound and SonarElectromagnetic SpectrumElectromagnetic FamilyRadio wavesMicrowavesInfraredVisible LightUltravioletX-raysGamma raysEM Spectrum SummaryRefractionRefractionLenses (uses of refraction)ReflectionNational 5 Data Sheet3924300384175MaterialSpeed in m s?1Aluminium5200Air340Bone4100Carbon dioxide270Glycerol1900Muscle1600Steel5200Tissue1500Water150000MaterialSpeed in m s?1Aluminium5200Air340Bone4100Carbon dioxide270Glycerol1900Muscle1600Steel5200Tissue1500Water1500Speed of light in materialsSpeed of sound in materialsMaterialSpeed in m s?1Air3·0 ? 108Carbon dioxide3·0 ? 108Diamond1·2 ? 108Glass2·0 ? 108Glycerol2·1 ? 108Water2·3 ? 108546735196850Gravitational field strength on the surface in N kg?1Earth9·8Jupiter23Mars3·7Mercury3·7Moon1·6Neptune11Saturn9·0Sun270Uranus8·7Venus8·900Gravitational field strength on the surface in N kg?1Earth9·8Jupiter23Mars3·7Mercury3·7Moon1·6Neptune11Saturn9·0Sun270Uranus8·7Venus8·9Gravitational field strengths3924300196215MaterialSpecific heat capacityin J kg?1 oC?1Alcohol2350Aluminium902Copper386Glass500Ice2100Iron480Lead128Oil2130Water418000MaterialSpecific heat capacityin J kg?1 oC?1Alcohol2350Aluminium902Copper386Glass500Ice2100Iron480Lead128Oil2130Water4180Specific heat capacity of materials546735196215MaterialSpecific latent heat of fusion in J kg?1Alcohol0·99 ? 105Aluminium3·95 ? 105Carbon dioxide1·80 ? 105Copper2·05 ? 105Iron2·67 ? 105Lead0·25 ? 105Water3·34 ? 10500MaterialSpecific latent heat of fusion in J kg?1Alcohol0·99 ? 105Aluminium3·95 ? 105Carbon dioxide1·80 ? 105Copper2·05 ? 105Iron2·67 ? 105Lead0·25 ? 105Water3·34 ? 105Specific latent heat of fusion of materialsMelting and boiling points of materialsMaterialMelting pointin oCBoiling pointin oCAlcohol?9865Aluminium6602470Copper10772567Glycerol18290Lead3281737Iron15372737Specific latent heat of vaporisation of materials54673526670MaterialSpecific latent heat of vaporisation in J kg?1Alcohol11·2 ? 105Carbon dioxide3·77 ? 105Glycerol8·30 ? 105Turpentine2·90 ? 105Water22·6 ? 10500MaterialSpecific latent heat of vaporisation in J kg?1Alcohol11·2 ? 105Carbon dioxide3·77 ? 105Glycerol8·30 ? 105Turpentine2·90 ? 105Water22·6 ? 105Radiation weighting factorsType of radiationRadiation weighting factoralpha20beta1fast neutrons10gamma1slow neutrons3X-rays1National 5 Relationship Sheet147212123061714587573502457556128835041081537408763249546621706318885You might notice that centi- (as in centimetres) is the “odd one out”. It doesn’t follow the pattern!Can you spot the pattern of the others?You might notice that centi- (as in centimetres) is the “odd one out”. It doesn’t follow the pattern!Can you spot the pattern of the others?-5080046755052. Prefixes and Scientific NotationOften in physics, we are dealing with very small or very large numbers. In order to save ourselves from writing such numbers as 0.0000000001 or 230 000 000, we use prefixes and scientific notation.PrefixSymbolScientific NotationOperationteraT1012x 1 000 000 000 000gigaG109x 1 000 000 000megaM106x 1 000 000kilok103x 1 000centic10-2÷ 100millim10-3÷ 1 000micro?10-6÷ 1 000 000nanon10-9÷ 1 000 000 000picop10-12÷ 1 000 000 000 000002. Prefixes and Scientific NotationOften in physics, we are dealing with very small or very large numbers. In order to save ourselves from writing such numbers as 0.0000000001 or 230 000 000, we use prefixes and scientific notation.PrefixSymbolScientific NotationOperationteraT1012x 1 000 000 000 000gigaG109x 1 000 000 000megaM106x 1 000 000kilok103x 1 000centic10-2÷ 100millim10-3÷ 1 000micro?10-6÷ 1 000 000nanon10-9÷ 1 000 000 000picop10-12÷ 1 000 000 000 000-5334015640051. SI unitsThere can be many ways of describing a quantity, for example distance: metres, miles, inches, yards etc. To avoid confusion, scientists have decided on using consistent units internationally. This means that when we are doing calculations involving, for example, a distance, we always use metres.This system is called the International System of Units — SI units for short.It is important that we always write down the units that we are using, and convert to theappropriate units when necessary. Here are some SI units we’ll be using:QuantitySymbolUnitUnit symbolDistancedmetremMassmkilogramkgTimetsecondss001. SI unitsThere can be many ways of describing a quantity, for example distance: metres, miles, inches, yards etc. To avoid confusion, scientists have decided on using consistent units internationally. This means that when we are doing calculations involving, for example, a distance, we always use metres.This system is called the International System of Units — SI units for short.It is important that we always write down the units that we are using, and convert to theappropriate units when necessary. Here are some SI units we’ll be using:QuantitySymbolUnitUnit symbolDistancedmetremMassmkilogramkgTimetsecondssUnits, Prefixes and Scientific NotationI can...use appropriate SI unitsuse prefixes: nano (n), micro (μ), milli (m), kilo (k), mega (M), giga (G).use scientific notationUnits, Prefixes and Scientific NotationI can...use appropriate SI unitsuse prefixes: nano (n), micro (μ), milli (m), kilo (k), mega (M), giga (G).use scientific notation50387254069548REMEMBER:minutes to seconds x minutes by 60hours to secondsx hours by (60 x 60) days to secondsx days by (24 x 60 x 60)years to secondsx years by 365 x 24 x 60 x 6000REMEMBER:minutes to seconds x minutes by 60hours to secondsx hours by (60 x 60) days to secondsx days by (24 x 60 x 60)years to secondsx years by 365 x 24 x 60 x 60024035754. Converting NumbersKilo or k = x 1000 or x 103Mega or M = x 1 000 000 or x 106Centi or c = ÷ 100 or x 10-2Mili or m = ÷ 1000 or x 10-3Example 1. Convert 3.2km into metres3.2km = 3.2 x 1000 = 3200m or3.2km = 3.2 x 103mExample 2. Convert 6.2ms into seconds6.2ms = 6.2 ÷ 1000 = 0.0062sor6.2ms = 6.2 x 10-3sPractice Questions1. Convert into metresa)4km =mor 4 x 10Choose an item.mb)12.6Mm =mor12.6Choose an item.mc)5.7cm =mor5.7 Choose an item.m1. Convert into kilograms (trickier)4000g =kgor4 Choose an item.kg0.1Mg=kgor1 Choose an item.kg5mg =kgor5 Choose an item.kg1. Convert into seconds2.2ms =sor2.2 Choose an item.s720ns=sor7.2 Choose an item.s0.1ms =sor1 Choose an item.s004. Converting NumbersKilo or k = x 1000 or x 103Mega or M = x 1 000 000 or x 106Centi or c = ÷ 100 or x 10-2Mili or m = ÷ 1000 or x 10-3Example 1. Convert 3.2km into metres3.2km = 3.2 x 1000 = 3200m or3.2km = 3.2 x 103mExample 2. Convert 6.2ms into seconds6.2ms = 6.2 ÷ 1000 = 0.0062sor6.2ms = 6.2 x 10-3sPractice Questions1. Convert into metresa)4km =mor 4 x 10Choose an item.mb)12.6Mm =mor12.6Choose an item.mc)5.7cm =mor5.7 Choose an item.m1. Convert into kilograms (trickier)4000g =kgor4 Choose an item.kg0.1Mg=kgor1 Choose an item.kg5mg =kgor5 Choose an item.kg1. Convert into seconds2.2ms =sor2.2 Choose an item.s720ns=sor7.2 Choose an item.s0.1ms =sor1 Choose an item.s-31752673. Scientific Notation Practice 2300000 = 2.3 x 10Choose an item.4560000000 = 4.56 x 10Choose an item.30000000 = 3 x 10Choose an item.806000 = 8.06 x 10Choose an item.0.005 = 5 x 10Choose an item.0.0000000047 = 4.7 x 10Choose an item.003. Scientific Notation Practice 2300000 = 2.3 x 10Choose an item.4560000000 = 4.56 x 10Choose an item.30000000 = 3 x 10Choose an item.806000 = 8.06 x 10Choose an item.0.005 = 5 x 10Choose an item.0.0000000047 = 4.7 x 10Choose an item.026708105. Transverse and Longitudinal WavesWaves carry Choose an item.. The substance the wave travels through is known as theChoose an item..Transverse:The particles oscillate (vibrate) at Choose an item. angles to the direction of the wave energy. Examples of transverse waves are Choose an item. and Choose an item. waves.Longitudinal:The particles oscillate back and Choose an item. in Choose an item. the direction as the motion of the wave (and the energy).An example of a longitudinal wave is Choose an item..005. Transverse and Longitudinal WavesWaves carry Choose an item.. The substance the wave travels through is known as theChoose an item..Transverse:The particles oscillate (vibrate) at Choose an item. angles to the direction of the wave energy. Examples of transverse waves are Choose an item. and Choose an item. waves.Longitudinal:The particles oscillate back and Choose an item. in Choose an item. the direction as the motion of the wave (and the energy).An example of a longitudinal wave is Choose an item..Wave PropertiesI can...state that energy can be transferred as wavesstate the difference between a transverse and a longitudinal wave and give examples of these.state the definitions of frequency, period, wavelength, amplitude and wave speed.determine the frequency, period, wavelength, amplitude and wave speed for transverse and longitudinal waves.do calculations involving d=vt, v=fλ and f=N/tdo calculations involving T=1/fWave PropertiesI can...state that energy can be transferred as wavesstate the difference between a transverse and a longitudinal wave and give examples of these.state the definitions of frequency, period, wavelength, amplitude and wave speed.determine the frequency, period, wavelength, amplitude and wave speed for transverse and longitudinal waves.do calculations involving d=vt, v=fλ and f=N/tdo calculations involving T=1/f30099006769100Question:what is the wave’s amplitude?what is its wavelength?Answers:A = 2mλ = 6 metres ÷ 3 waves = 2m00Question:what is the wave’s amplitude?what is its wavelength?Answers:A = 2mλ = 6 metres ÷ 3 waves = 2m06563995Example 1Look at this water wave00Example 1Look at this water wave006. Wave CharacteristicsWe use the following terms to describe parts of the waveWave PropertyDefinitionCrestHighest point of a waveTroughLowest point of a waveWavelength (λ)Length of a waveAmplitude (A)Height of a wave006. Wave CharacteristicsWe use the following terms to describe parts of the waveWave PropertyDefinitionCrestHighest point of a waveTroughLowest point of a waveWavelength (λ)Length of a waveAmplitude (A)Height of a wave2667002461260Choose an item.00Choose an item.19431004413885Choose an item.00Choose an item.43148254185285Choose an item.00Choose an item.17621251061085Choose an item.00Choose an item.42284651285875Choose an item.00Choose an item.052070008. Frequency Example:What is the frequency if 400 waves are produced in 20s?N = 400f=Ntt = 20sf=40020f = ?f=20Hz008. Frequency Example:What is the frequency if 400 waves are produced in 20s?N = 400f=Ntt = 20sf=40020f = ?f=20Hz364426568306954234815683069534442407028180Hz020000Hz41586157028180s020000s104775588645036290251120140m020000m3505200135255000362902520859753048000208597535528252276475s020000s28860752266950ms-1020000ms-1007. Wave SpeedThe distance travelled by a wave travelling at a constant speed can be calculated using:Example:The crest of a water wave moves a distance of 4m in 10 seconds. Calculate the speed of the wave.d = 4md=v x tt = 10s4=v x 10v = ?v= 104= 2.5ms-1The speed of sound in air is 340ms-1 and the speed of light in air is 300 000 000ms-1(or 3 x 108ms-1). Light travels approximately 1 million times faster than sound!007. Wave SpeedThe distance travelled by a wave travelling at a constant speed can be calculated using:Example:The crest of a water wave moves a distance of 4m in 10 seconds. Calculate the speed of the wave.d = 4md=v x tt = 10s4=v x 10v = ?v= 104= 2.5ms-1The speed of sound in air is 340ms-1 and the speed of light in air is 300 000 000ms-1(or 3 x 108ms-1). Light travels approximately 1 million times faster than sound!3619500189230030511752019300Hz020000Hz325120018923000036163251969135s020000s408622565366904064000588010042037005664200ms-1020000ms-13613150653986533528006710045Hz020000Hz40671756710045m020000m160737677785from knowledgefrom knowledge-73879464386510. The Wave EquationWe can also find the speed of a wave using its frequency and Choose an item..ExampleMicrowaves have a frequency of 9.4 GHz. Calculate their wavelength. v = 3 X 108v=f x λf = 9.4 x 1093 X 108=19.4 X 109λ = ?λ = 0.032m 0010. The Wave EquationWe can also find the speed of a wave using its frequency and Choose an item..ExampleMicrowaves have a frequency of 9.4 GHz. Calculate their wavelength. v = 3 X 108v=f x λf = 9.4 x 1093 X 108=19.4 X 109λ = ?λ = 0.032m 9613962879-90192472099. PeriodWe can consider the case for just one wave. The number of waves is 1 and the time taken is called the Choose an item.. The period is measured in Choose an item. Also ExampleA certain breed of bat emits ultrasound waves with a period of 23?s. Calculate the frequency of the ultrasound.T = 23 X 10-6sf=1Tf=1/23 X 10-6f = ?f=43478Hz = 43.5 KhZ009. PeriodWe can consider the case for just one wave. The number of waves is 1 and the time taken is called the Choose an item.. The period is measured in Choose an item. Also ExampleA certain breed of bat emits ultrasound waves with a period of 23?s. Calculate the frequency of the ultrasound.T = 23 X 10-6sf=1Tf=1/23 X 10-6f = ?f=43478Hz = 43.5 KhZ009. Wave Properties SummaryQuantitySymbolUnitUnit SymbolDefinitionWavelengthChoose an item.metreChoose an item.The Choose an item. between any two repeating points on the waveAmplitudeAChoose an item.mThe Choose an item. of a wave from the middle lineWave speedChoose an item.Choose an item.ms-1The Choose an item. the wave has travelled per unit timeFrequencyfChoose an item.Choose an item.The number of waves passing a point in Choose an item. secondPeriodChoose an item.secondsChoose an item.The Choose an item. it takes one wave to pass a point 009. Wave Properties SummaryQuantitySymbolUnitUnit SymbolDefinitionWavelengthChoose an item.metreChoose an item.The Choose an item. between any two repeating points on the waveAmplitudeAChoose an item.mThe Choose an item. of a wave from the middle lineWave speedChoose an item.Choose an item.ms-1The Choose an item. the wave has travelled per unit timeFrequencyfChoose an item.Choose an item.The number of waves passing a point in Choose an item. secondPeriodChoose an item.secondsChoose an item.The Choose an item. it takes one wave to pass a point 0168402012. Diffraction All waves will Choose an item. around obstacles placed in their way. This bending effect is called ___________. The longer the wavelength the __________ they diffract. Example: Choose an item. Choose an item. A wave with wavelength of 4m will diffract ________ than a wave with wavelength of 2m. A wave of frequency 1000Hz will diffract ________ than a wave of frequency 50Hz. The waves used for TVs are _______ than those used for radios. This is why you might be able to receive radio signals in the shadow of hills, where you wouldn’t get TV signalNOTE: Diffraction is why we can hear the sound from objects around a corner but cannot see them. Sound waves have a much lower frequency than light waves (or any other part of the electromagnetic spectrum) and so a much longer wavelength.0012. Diffraction All waves will Choose an item. around obstacles placed in their way. This bending effect is called ___________. The longer the wavelength the __________ they diffract. Example: Choose an item. Choose an item. A wave with wavelength of 4m will diffract ________ than a wave with wavelength of 2m. A wave of frequency 1000Hz will diffract ________ than a wave of frequency 50Hz. The waves used for TVs are _______ than those used for radios. This is why you might be able to receive radio signals in the shadow of hills, where you wouldn’t get TV signalNOTE: Diffraction is why we can hear the sound from objects around a corner but cannot see them. Sound waves have a much lower frequency than light waves (or any other part of the electromagnetic spectrum) and so a much longer wavelength.2946400274320037846002540000wavefronts00wavefronts34036002997200The wavefronts bend around the object as it passes. NOTE: The closer the wavefronts are together, the shorter the wavelength (and so higher the frequency of the waves).020000The wavefronts bend around the object as it passes. NOTE: The closer the wavefronts are together, the shorter the wavelength (and so higher the frequency of the waves).00DIFFRACTION 00DIFFRACTION 0186182012. The Speed of Sound Sound travels as Choose an item. waves. Sound travels through Choose an item., Choose an item. and Choose an item., but it will not travel through a Choose an item.. Experiment to measure the speed of sound Connect two microphones to an Choose an item.. Measure the distance between microphones using a Choose an item.. Make a loud Choose an item.. When the sound gets to microphone A the timer Choose an item.. When sound gets to microphone B the timer Choose an item.. Use the Choose an item. between the microphones and the Choose an item. taken by the sound to get from microphone A to microphone B to calculate the speed of sound using: The speed of sound in air is Choose an item.. The speed of light in air is Choose an item.ms-1. Light is much faster than Choose an item.. In a thunderstorm the lightning and thunder are made at the same Choose an item.. We see the Choose an item. first, because the light waves travel Choose an item. than the sound, so it gets to us first.0012. The Speed of Sound Sound travels as Choose an item. waves. Sound travels through Choose an item., Choose an item. and Choose an item., but it will not travel through a Choose an item.. Experiment to measure the speed of sound Connect two microphones to an Choose an item.. Measure the distance between microphones using a Choose an item.. Make a loud Choose an item.. When the sound gets to microphone A the timer Choose an item.. When sound gets to microphone B the timer Choose an item.. Use the Choose an item. between the microphones and the Choose an item. taken by the sound to get from microphone A to microphone B to calculate the speed of sound using: The speed of sound in air is Choose an item.. The speed of light in air is Choose an item.ms-1. Light is much faster than Choose an item.. In a thunderstorm the lightning and thunder are made at the same Choose an item.. We see the Choose an item. first, because the light waves travel Choose an item. than the sound, so it gets to us first.69850SOUND 00SOUND 427990064465200200000417830015. Noise and Decibels The larger the amplitude the Choose an item. the sound. Sound level or loudness is measured in units called Choose an item. or Choose an item. for short. Normal conversation is Choose an item. dB. Danger level is Choose an item. dB. A loud concert is Choose an item. dB. Loud sounds can damage your Choose an item., so you should wear Choose an item. protectors, such as Choose an item. plugs, ear defenders or noise Choose an item. headphones. Choose an item. is the name we give to any sounds which we don’t want, such as traffic that could cause hearing damageSource of soundSound level (dB) Threshold of pain140Choose an item.120Pneumatic drill100Noise pollution90Choose an item.60Choose an item.30Background noise at homeChoose an item.0015. Noise and Decibels The larger the amplitude the Choose an item. the sound. Sound level or loudness is measured in units called Choose an item. or Choose an item. for short. Normal conversation is Choose an item. dB. Danger level is Choose an item. dB. A loud concert is Choose an item. dB. Loud sounds can damage your Choose an item., so you should wear Choose an item. protectors, such as Choose an item. plugs, ear defenders or noise Choose an item. headphones. Choose an item. is the name we give to any sounds which we don’t want, such as traffic that could cause hearing damageSource of soundSound level (dB) Threshold of pain140Choose an item.120Pneumatic drill100Noise pollution90Choose an item.60Choose an item.30Background noise at homeChoose an item.0014. Waveforms We can display sound waves on an oscilloscope screen. The Choose an item. of a sound wave corresponds to the loudness of the sound. The Choose an item. of the waves corresponds to the pitch of the sound. Choose an item.Choose an item.Choose an item.Choose an item.Choose an item.Choose an item.Choose an item.Choose an item.Amplifiers can be used to make a sound Choose an item.. This increases the Choose an item., but doesn’t change the Choose an item. of the sound.0014. Waveforms We can display sound waves on an oscilloscope screen. The Choose an item. of a sound wave corresponds to the loudness of the sound. The Choose an item. of the waves corresponds to the pitch of the sound. Choose an item.Choose an item.Choose an item.Choose an item.Choose an item.Choose an item.Choose an item.Choose an item.Amplifiers can be used to make a sound Choose an item.. This increases the Choose an item., but doesn’t change the Choose an item. of the sound.49276004965700020000509270037338000200000016. Ultrasound and SonarHumans can hear sound waves with frequencies between Choose an item. and Choose an item. Hz. Frequencies above 20 000Hz are called Choose an item., and frequencies below 20 Hz are called Choose an item.. Put the two names in the correct boxes on the diagram.When ultrasound travels from one medium into another some of it Choose an item. back. We can use this fact for medical imagining, such as looking at unborn Choose an item.. We can also use ultrasound to break up Choose an item. stones. Sonar Choose an item. is used on ships and submarines to detect ______, other vessels, or the seabed. A pulse of Choose an item. is sent out from the ship. It Choose an item. off the seabed or shoal of fish and the echo is detected. We can use the time taken for the sound to travel back to work out the depth. Bats use the same idea to work out their surroundings.0016. Ultrasound and SonarHumans can hear sound waves with frequencies between Choose an item. and Choose an item. Hz. Frequencies above 20 000Hz are called Choose an item., and frequencies below 20 Hz are called Choose an item.. Put the two names in the correct boxes on the diagram.When ultrasound travels from one medium into another some of it Choose an item. back. We can use this fact for medical imagining, such as looking at unborn Choose an item.. We can also use ultrasound to break up Choose an item. stones. Sonar Choose an item. is used on ships and submarines to detect ______, other vessels, or the seabed. A pulse of Choose an item. is sent out from the ship. It Choose an item. off the seabed or shoal of fish and the echo is detected. We can use the time taken for the sound to travel back to work out the depth. Bats use the same idea to work out their surroundings.50927001539240Choose an item.00Choose an item.3429001536700Choose an item.00Choose an item.0252730017. Electromagnetic Family Electromagnetic Choose an item. describes a range, or a family of waves, which all travel at the same speed: Choose an item. x 108 ms-1. This is known as the speed of Choose an item. and is given the symbol c. This is a universal speed limit—NOTHING can travel faster than c. Our eyes are only able to detect one small part of the spectrum (this is the colours that we see). Here is the full spectrum. Fill in the names of the missing waves. Radio waves have the longest Choose an item.. Gamma rays have the shortest Choose an item. and therefore the highest Choose an item.. As the frequency of the wave increases the wave has more Choose an item.. This means that Choose an item. have the most energy and Choose an item. waves have the least. In the spectrum the waves which diffract the most are Choose an item. waves, because they have the Choose an item. wavelengths. 0017. Electromagnetic Family Electromagnetic Choose an item. describes a range, or a family of waves, which all travel at the same speed: Choose an item. x 108 ms-1. This is known as the speed of Choose an item. and is given the symbol c. This is a universal speed limit—NOTHING can travel faster than c. Our eyes are only able to detect one small part of the spectrum (this is the colours that we see). Here is the full spectrum. Fill in the names of the missing waves. Radio waves have the longest Choose an item.. Gamma rays have the shortest Choose an item. and therefore the highest Choose an item.. As the frequency of the wave increases the wave has more Choose an item.. This means that Choose an item. have the most energy and Choose an item. waves have the least. In the spectrum the waves which diffract the most are Choose an item. waves, because they have the Choose an item. wavelengths. 26670005107940Choose an item.00Choose an item.54864004394200Choose an item.00Choose an item.19558004394200Choose an item.00Choose an item.37719004406900Choose an item.00Choose an item.9906004406900Choose an item.00Choose an item.31496006899910Choose an item.00Choose an item.31496006428740Choose an item.00Choose an item.31496005969000Choose an item.00Choose an item.00THE ELECTROMAGNETIC SPECTRUM 00THE ELECTROMAGNETIC SPECTRUM 0762000021. Visible LightThis light is made up of a range of different Choose an item.. Red has a Choose an item. wavelength than blue light. A concentrated beam of visible light of one wavelength is called a Choose an item. beam. It can be used in laser eye Choose an item..0021. Visible LightThis light is made up of a range of different Choose an item.. Red has a Choose an item. wavelength than blue light. A concentrated beam of visible light of one wavelength is called a Choose an item. beam. It can be used in laser eye Choose an item..5321300775970002000051943005791200000566674020. InfraredAnother name for infrared radiation is Choose an item.. It can be detected by a thermometer. In medicine it can be used in heat treatment of damaged Choose an item. tissue. Rescue services can use Choose an item. imaging cameras to find people in dark or smoky places. The signal between your Choose an item. and TV is also transmitted using infrared waves.0020. InfraredAnother name for infrared radiation is Choose an item.. It can be detected by a thermometer. In medicine it can be used in heat treatment of damaged Choose an item. tissue. Rescue services can use Choose an item. imaging cameras to find people in dark or smoky places. The signal between your Choose an item. and TV is also transmitted using infrared waves.0369570019. MicrowavesMicrowaves are used to carry signals up to Choose an item. in space and between our mobile phones! We can also use them to Choose an item. up food in a microwave oven. They are emitted by Choose an item. circuits, and can be detected using an Choose an item., just like radio waves. Microwaves could cause Choose an item., if concentrated.0019. MicrowavesMicrowaves are used to carry signals up to Choose an item. in space and between our mobile phones! We can also use them to Choose an item. up food in a microwave oven. They are emitted by Choose an item. circuits, and can be detected using an Choose an item., just like radio waves. Microwaves could cause Choose an item., if concentrated.4483100377190002000005080018. Radio wavesRadio waves have long Choose an item., so they are good at Choose an item. round hills and buildings. This makes them ideal for carrying radio and Choose an item. programmes to your house. Radio waves are emitted by Choose an item. circuits and some stars. They can be detected by using an Choose an item.. Radio waves are safe, in fact there are radio waves passing all around us right now!0018. Radio wavesRadio waves have long Choose an item., so they are good at Choose an item. round hills and buildings. This makes them ideal for carrying radio and Choose an item. programmes to your house. Radio waves are emitted by Choose an item. circuits and some stars. They can be detected by using an Choose an item.. Radio waves are safe, in fact there are radio waves passing all around us right now!0459740024. Gamma RaysGamma rays are created in the nuclei of Choose an item., during radioactive decay. Gamma rays can be used to kill Choose an item. cells in your body. Chemicals emitting gamma radiation can also be injected into your Choose an item. stream. A gamma camera picks up the Choose an item. radiation being emitted by the chemicals and creates an image of Choose an item. flow in your body. This is called a radioactive Choose an item.. Overexposure to gamma rays can cause Choose an item.. We can detect gamma rays using a Geiger–Müller tube.0024. Gamma RaysGamma rays are created in the nuclei of Choose an item., during radioactive decay. Gamma rays can be used to kill Choose an item. cells in your body. Chemicals emitting gamma radiation can also be injected into your Choose an item. stream. A gamma camera picks up the Choose an item. radiation being emitted by the chemicals and creates an image of Choose an item. flow in your body. This is called a radioactive Choose an item.. Overexposure to gamma rays can cause Choose an item.. We can detect gamma rays using a Geiger–Müller tube.4305300647065002000043053004787900020000458470023876000200000212090023. X-RaysX-rays pass through most tissue and cause photographic film to turn Choose an item.. However, X-rays are absorbed by Choose an item. in your body, so the photographic film behind bones stays white, allowing doctors to detect, for example, broken bones. Overexposure to X-rays can cause Choose an item., which is why there is a limit to how many X-rays you can have in one year. X-rays are created when very Choose an item. electrons hit a metal target. 0023. X-RaysX-rays pass through most tissue and cause photographic film to turn Choose an item.. However, X-rays are absorbed by Choose an item. in your body, so the photographic film behind bones stays white, allowing doctors to detect, for example, broken bones. Overexposure to X-rays can cause Choose an item., which is why there is a limit to how many X-rays you can have in one year. X-rays are created when very Choose an item. electrons hit a metal target. 56642009271000200005321300254000200000022. Ultraviolet Most of our ultraviolet radiation comes from the Choose an item.. Too much of it can Choose an item. the skin, or even worse, cause skin Choose an item.. This is why it’s advised to wear sun Choose an item. when outdoors. Special Choose an item. chemicals can be printed on important items, such as money, as Choose an item. markings. These markings only show up under Choose an item. light. Ultraviolet light can be used to treat skin conditions, like Choose an item..0022. Ultraviolet Most of our ultraviolet radiation comes from the Choose an item.. Too much of it can Choose an item. the skin, or even worse, cause skin Choose an item.. This is why it’s advised to wear sun Choose an item. when outdoors. Special Choose an item. chemicals can be printed on important items, such as money, as Choose an item. markings. These markings only show up under Choose an item. light. Ultraviolet light can be used to treat skin conditions, like Choose an item..25. Electromagnetic Spectrum SummaryType of WaveSourceDetectorApproximate WavelengthUseDanger of ExposureChoose an item.1km – 1mChoose an item.1cm (10-2m)Choose an item.10?m (10-5m)Visible Light~700nm – Red~550nm - Green~500nm – Blue~400nm - VioletChoose an item.10nm (10-8m)Choose an item.0.1nm (10-10m)Choose an item.10pm (10-12m)00Examples00Examples265620554571900024549104025900000181610026. RefractionRefraction is the process where the Choose an item. of a wave changes as it travels from one medium into a different medium (i.e. air into glass). If the light travels at an angle to the normal from one medium into another then it’s Choose an item. also changes. The frequency of the light does not change. Here is a diagram showing a beam of light travelling from air into the block then back into air. Line Q is drawn at Choose an item. to the boundary. It is called the Choose an item.. All angles are measured from the normal to the ray of light. angle w = angle of Choose an item. angle x = angle of Choose an item. angle y = angle of Choose an item. angle y = angle of Choose an item.0026. RefractionRefraction is the process where the Choose an item. of a wave changes as it travels from one medium into a different medium (i.e. air into glass). If the light travels at an angle to the normal from one medium into another then it’s Choose an item. also changes. The frequency of the light does not change. Here is a diagram showing a beam of light travelling from air into the block then back into air. Line Q is drawn at Choose an item. to the boundary. It is called the Choose an item.. All angles are measured from the normal to the ray of light. angle w = angle of Choose an item. angle x = angle of Choose an item. angle y = angle of Choose an item. angle y = angle of Choose an item.00REFRACTION00REFRACTION37592004508500NOTE: It is the refraction of white light through raindrops (with a similar shape to a prism) that causes rainbow to be formed.020000NOTE: It is the refraction of white light through raindrops (with a similar shape to a prism) that causes rainbow to be formed.00This effect is used in lenses or prisms as shown below.Ray bends towards normal in prism.i > r moving from air to glassΘa in air > θp in PerspexNotice that in all the diagrams above as light moves from air into glass/perspex it bends towards the normal.As white light (the light we get from the sun) is made up of several different wavelength of light.Each wavelength refracts be a different amount (red refracts the least and violet refracts the most) and so when white light is passed through a prism, a spectrum is produced.Above a certain angle of incidence, refraction no longer occurs, and instead the light wave is reflected back into the medium where it came from. This is known as total internal reflection. The minimium angle of incidence that causes the wave to undergo total internal reflection is called the critical angle.Total internal reflection is used in optical fibres. Optical fibres can be used for communication or in medical applications to allow doctors to see into the body. One bundle of fibres carries light into the body whilst another carries the light back out of the body. This instrument is known as an endoscope.00This effect is used in lenses or prisms as shown below.Ray bends towards normal in prism.i > r moving from air to glassΘa in air > θp in PerspexNotice that in all the diagrams above as light moves from air into glass/perspex it bends towards the normal.As white light (the light we get from the sun) is made up of several different wavelength of light.Each wavelength refracts be a different amount (red refracts the least and violet refracts the most) and so when white light is passed through a prism, a spectrum is produced.Above a certain angle of incidence, refraction no longer occurs, and instead the light wave is reflected back into the medium where it came from. This is known as total internal reflection. The minimium angle of incidence that causes the wave to undergo total internal reflection is called the critical angle.Total internal reflection is used in optical fibres. Optical fibres can be used for communication or in medical applications to allow doctors to see into the body. One bundle of fibres carries light into the body whilst another carries the light back out of the body. This instrument is known as an endoscope.-635002540027. LensesLenses make use of the effect of refraction that causes light to change direction.When light rays pass through a convex lens they come together (converge). When light rays pass through a concave lens they move apart (diverge). The more curved a lens is the greater the effect on the light rays.Lenses can be used to correct sight problems0027. LensesLenses make use of the effect of refraction that causes light to change direction.When light rays pass through a convex lens they come together (converge). When light rays pass through a concave lens they move apart (diverge). The more curved a lens is the greater the effect on the light rays.Lenses can be used to correct sight problems-7620012573000-63500-27940028. ReflectionThe law of reflection states that the angle of incidence, i, is equal to the angle of reflection, r. Remember that all angles in a ray diagram are measured from the normal to the line representing the ray (wave). Reflection from curved mirrors (reflectors)All waves reflect and if we examine the reflection of light on a curved mirror we can see how they can be used to spread light out or focus it to a point.Concave reflectors are used to focus light beams to a central focal point. This principle is used for satellite dish receivers on the side of house that collect and focus signals from satellite to a an aerial at the centre of the dish.Convex reflectors are used to spread light out. You may find these in the corner of small shops, or sharp bends in roads, allowing you to get a clear view around corners.0028. ReflectionThe law of reflection states that the angle of incidence, i, is equal to the angle of reflection, r. Remember that all angles in a ray diagram are measured from the normal to the line representing the ray (wave). Reflection from curved mirrors (reflectors)All waves reflect and if we examine the reflection of light on a curved mirror we can see how they can be used to spread light out or focus it to a point.Concave reflectors are used to focus light beams to a central focal point. This principle is used for satellite dish receivers on the side of house that collect and focus signals from satellite to a an aerial at the centre of the dish.Convex reflectors are used to spread light out. You may find these in the corner of small shops, or sharp bends in roads, allowing you to get a clear view around corners. ................
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