Flashcards
Untitled
Cards in this deck (136)
- 1at what angle are longitudinal waves to the direction of energy transfer of the waveparallel
- 2at what angle are transverse waves to the direction of energy transfer to the wave90 degrees (perpendicular)
- 3give three examples of a transverse waveany 3 from : light wave
waves on strings
ripples on water
a slinky WIGGLED UP AND DOWN - 4give three examples of a longitudinal waveany 3 from: sound waves
ultrasound
shock waves
a slinky WHEN YOU PUSH THE END - 5whats the name of the squashed up bit in a longitudinal wave? and whats the name of the stretched out bit with fewer particles1) compression
2) rarefraction - 6all waves can be...reflected, refracted or diffracted
- 7what dos reflection of light do?allow us to see things
- 8what is the law of reflectionangle of incidence = angle of refraction
- 9where are the angle of incidence and angle of reflection in a reflected raybetween the ray itself and the NORMAL
- 10what makes an image virtual?if it is behind the mirror or lens
- 11when do waves diffract and what does diffraction meanwhen they pass through a gap or pass an object, it means to spread out
- 12what happens when identical sets of waves meetif they're going in the same direction: they disturb each other or they reinforce each other
if they're going in opposite directions:
they cancel each other out - 13how do electromagnetic waves travel in dense materialmore slowly
- 14how do sound waves travel in denser materialsfaster
- 15what colour light does a triangular prism disperse into different coloursit disperses white light
- 16what is the refracted indexit tells you how fast light travels in a certain material
- 17how is light sent across optical fibresusing total internal reflection
- 18what does total internal reflection depend onthe angle of incidence to be bigger than the critical angle
- 19what determines the critical anglethe refractive index of the material.
high RI = low critical angle - 20what do endoscopes usebundles of optical fibres
- 21what is the job of the two different optical fibres in an endoscopeone carries light to the area of interest and one carries the image back so it can be viewed
- 22what is the advantage of optical fibres now in medical industries that wasn't possible beforedoctors ad surgeons can now preform keyhole surgery
- 23what is the spectrum of EM wavesradio waves
microwaves
infra-red
visible light
ultra violet
x-rays
gamma - 24if an EM wave has a higher frequency what is there wavelength long or shortshort
- 25what are radio waves used forcommunication, TV , fm radio , bluetooth
- 26what are microwaves used forsatellite communication and mobile phones
- 27what are infra-red waves used forremote controls and optical fibres e.g. a phone line
- 28what is visible light used forphotography
- 29what does the aperture of a camera docontrols how much light enters the camera
- 30what does the shutter speed of a camera controlhow long the film or sensor of the camera is exposed to light
- 31what is ultra-violet radiation used forused for security marking like on bank notes or using security pens for marking your stuff
- 32what do x-rays doallows us to see inside things
- 33what are gamma rays used forto sterilise hospital equipment
- 34is an EM wave with a high frequency more or less harmful than one with a lower frequencymore
- 35how can microwaves effect the human bodythey can heat human body tissue
- 36what can ultraviolet radiation do to the bodycan damage surface cells are cause blindness
- 37what can infrared do to your bdyburn skin
- 38what can X-rays or gamma rays do to the bodythey ca cause genetic mutation, tissue damage or even cancer
- 39give three different uses of X-raysCT scans
medical diagnosis
treat cancer - 40what method do X-rays use to beat cancer and how does this workionisation, kills living cells, so the right dose will kill the cancer cells
- 41what causes sound wavesvibrating objects
- 42what type of wave is a sound wavelongitudinal wave
- 43what is the meaning of vacuumthere are no particles
- 44what type of things will sound waves be reflected byhard flat surfaces
- 45when do sound waves diffractwhen they enter different material
- 46having a higher frequency of sound waves produces a ???? pitchhigher
- 47what is frequency a measure of in sound wavesthe number of complete vibrations each second
- 48what does the loudness of a sound depend on????amplitude
- 49what happens to ultrasound waves at a boundary between mediathey get partially reflected
- 50what is ultrasound used for in medal industry (2 things)producing video images of foetuses and the turn large kidney stones into sand like particles
- 51what are the two different types of lensconverging(convex)
diverging - 52which image is the convex onethe one that bulges out
- 53which is the diverging lensthe one that caves inwards
- 54what three things do you need to do when describing a lenssay wether its real or virtual
say weather its upright or inverted
say whether its magnified or diminished - 55what can be made from a converging lensmagnifying glass
- 56what can't you do with a virtual imageproject it onto a screen
- 57what is the function of the corneais a 'transparent window' with a convex shape and a high refractive index. It does most of the eyes focusing
- 58what is the function of the iristhe iris is the coloured part of the eye, it is made up of muscles that control the size of the pupil. This, therefore, controls the light intensity entering the eye.
- 59describe what the lens in the eye doesthe ;end changes shapes to focus light from different objects at varying distances. Its connected to the ciliary muscle by suspensory ligaments and when theses muscles contact the lens relaexes and gets fat. vice versa
- 60describe the function of the retinaimages are formed here, it is covered in light sensitive cells which detect light and send signals to the brain to be interpreted.
- 61what is the name for the furthest distance an eye can focus of comfortablythe far point
- 62what is the near point and what length is it25cm, its the shortest distance that the eye can focus on comfortably
- 63in a camera what type of image is formed on the filma real image, smaller and inverted
- 64what type of lens is used to correct short sightdiverging lens
- 65what type of lens corrects long sightconverging lens
- 66what causes short sightednessthe eyeball being too long or the cornea being too powerful
- 67what causes people to be long sightedthe eyeball being too short or the cornea being too weak
- 68why does a laser help inn eye surgeryit can vaporise some of the cornea to change its shape
- 69whats red shiftwhen there is an increase un wavelength of light coming from other galaxies and the patterns have been pushed towards the red end of the spectrum
- 70how does the doppler effect workwhen an object is moving towards you, its frequency will seem higher and its wavelength will seem shorter, but when its moving away, its frequency will see lower and its wavelength longer
- 71is red shift greater or smaller from a galaxy further awaygreater
- 72what does an increase in red shift show about galaxies further awaythey're moving away from us faster than near ones,
- 73what can red shift show usthat the world bay have began from a very small initial point (big bang)
- 74when did the big bang happen14 billions years agp
- 75whats the theory called that suggests the universe has always been the same????the steady state theory
- 76what radiation is strong evidence that the big bang happenedcosmic microwave background radiation
- 77What is the specific heat capacitythe amount of energy something can store
- 78what is specific latent heatthe amount of energy needed to change the state of 1kg of it without a temperature change
- 79what is specific latent heat of vaporisationthe amount of energy needed to boil something of 1kg without changing the temp
- 80what surfaces absorb infrared radiation wellblack matte
- 81what surfaces do to absorb infra red radiation welllight shiny
- 82are light shiny surfaces good emitters of infraredno
- 83what type of state does conduction occursolids
- 84what state does convection occurliquids and gases
- 85what are bimetallic strips used inthermostats
- 86what is a thermostata device that automatically regulates temperature, or that activates a device when the temperature reaches a certain point.
- 87what can energy not be?created or destroyed
- 88give 3 ways of being energy efficient in the homedouble glazing
loft insulation
hot water tank jacket
draught-proofing
cavity wall insulation - 89in a good insulator would the u-value be high or lowlow
- 90describe conductionwhere abrading particles pass on extra kinetic energy (or heat) to neighbouring particles
- 91what is the definition of currentthe flow of electrical charge around a circuit
- 92what is potential differencedriving force that pushes a current round also known as volts
- 93what is resistance in a circuitanything that slows the circuit down
- 94what is a basic circuit used fortesting components
- 95an increase in what causes an increase in resistancetemperature
- 96why does resistance increase with temperaturethe ions vibrate more vigorously and so its harder for the charge carriers or particles to get through
- 97describe a diode and its functionmade out of silicon
used to regulate voltage
only lets current flow in one direction
useful in electronic circuits - 98what are light emitting diodes (LED's) useful forremotes, traffic lights, digital clocks
- 99diodes change ??? to ???change alternating curent to direct current
- 100what are light dependant resistors used for and why?night lights etc because in darkness they have a high resistance and in bright light they have a low resistance
- 101why are thermistors good for car engine temp sensors or thermostatesbecause in high temps the resistance drops and in low temps the resistance increases
- 102what is the brown wire?live wire
- 103what is the blue wireneutral wire
- 104what is the yellow and green wireearth wire
- 105what are the metal parts of a plug made ofcopper or brass
- 106describe how the earth wire and fuse work togetherfault allows live wire to touch metal case
big current flows out through the earth wire
and a big current surges to the earth wire
The big surge in current melts the fuse which isolates the appliance from the live wire - 107what are the advantages of a RCCB circuit breaker over a fusethey operate faster than fuses
and they work for small current changes that won't work to melt a fuse, so more effective at protecting against electrocution - 108what is the national grida network of cables and pylons that covers Britain getting electricity to homes everywhere
- 109why is using a high current bad in the national gridlots of energy is lost via heat
- 110do transformers work on alternating current or direct currentalternating current
- 111what is a magnetic fielda region where magnetic materials feel a force
- 112what direction do magnetic field lines go innorth to south
- 113what can you use to measure magnetic field pattersa compass or iron fillings
- 114what two things speed up a simple electric motormore current
stronger magnetic field - 115give three uses of an electric motorfan
cd player
cement mixer
hair dryer
drill - 116what does the generator effect to to a conductorit creates a potential difference
- 117what four things can you increase to get a bigger voltagethe strength of the magnet
the area of the coil
the speed of movement
the number of turns on the coil - 118what are the slip rings and brushes used for in an AC generatorso the contacts don't swap every half turn
- 119what does a dc generator use to make sure the contacts swap every half turnsplit-ring commutator
- 120what does the iron core of a transformer docarry the magnetic field
- 121what are switch mode transformers used inchargers and power supplies
- 122what three types of radiation will harm living cellsalpha, gamma, beta
- 123what does the collisions of radiation with cells causeionisation
- 124why is alpha less harmful to the body than beta or gammaalpha can't penetrate skin
- 125how can you take precaution when handling radioactive materialsnever allow skin contact, always use prongs
hold at arms length
keep it pointing away from the body
store them in a lead box - 126what is an alpha particlea helium nuclei
- 127are beta particles a proton, electron or neutronelectron
- 128what blocks an alpha raya piece of paper
- 129what blocks a gamma raythick lead
- 130what blocks a beta rayaluminium
- 131what is half lifethe average time taken for the number of nuclei in a radioactive isotope to halve
- 132what type of radiation do smoke detectors use ?alpha, if there is a fire the smoke will stop the current and sound an alarm
- 133what is radiotherapy used for and what type of radiation does it usegamma rays & it's used for the treatment of cancer
- 134what is nuclear fisiionthe splitting up of a big atomic nuclei
- 135what is nuclear FUSIONthe joining of small atomic nuclei
- 136where doe all the energy released in stars come from? what processnuclear fusion
Information
- Description
- Flashcards on Untitled, created by libbybailey on 19/05/2015.
- Created by
- libbybailey
- Views
- 1
- Rating