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c29f3f58_Flashcards_about_NHA_CCMA_Exam__Answer
[Question] During depolarization the electrical impulses flow [Answer]
From the endo to the myo to the epicardium
[]
Flashcards about NHA CCMA Exam
Answer
http://www.studystack.com/flashcard-593521
2/1438042982745.46_20150728002302-00146-ip-10-236-191-2_721638876_3.json
c29f3f58_Flashcards_about_NHA_CCMA_Exam__Answer
[Question] During repolarization the electrical impulses flow from... [Answer]
The epicardium towards the endocardium
[]
Flashcards about NHA CCMA Exam
Answer
http://www.studystack.com/flashcard-593521
2/1438042982745.46_20150728002302-00146-ip-10-236-191-2_721638876_3.json
c29f3f58_Flashcards_about_NHA_CCMA_Exam__Answer
[Question] What fires at 40-60 bpm [Answer]
AV junction, bundle of HIS
[]
Flashcards about NHA CCMA Exam
Answer
http://www.studystack.com/flashcard-593521
2/1438042982745.46_20150728002302-00146-ip-10-236-191-2_721638876_3.json
c29f3f58_Flashcards_about_NHA_CCMA_Exam__Answer
[Question] Which are unipolar leads? [Answer]
aVR, aVL,aVF
[]
Flashcards about NHA CCMA Exam
Answer
http://www.studystack.com/flashcard-593521
2/1438042982745.46_20150728002302-00146-ip-10-236-191-2_721638876_3.json
c29f3f58_Flashcards_about_NHA_CCMA_Exam__Answer
[Question] 0.1mV on EKG paper measures [Answer]
1mm
[]
Flashcards about NHA CCMA Exam
Answer
http://www.studystack.com/flashcard-593521
2/1438042982745.46_20150728002302-00146-ip-10-236-191-2_721638876_3.json
c29f3f58_Flashcards_about_NHA_CCMA_Exam__Answer
[Question] On the vertical axis 1 large square equals what? [Answer]
5mm(0.5mV)
[]
Flashcards about NHA CCMA Exam
Answer
http://www.studystack.com/flashcard-593521
2/1438042982745.46_20150728002302-00146-ip-10-236-191-2_721638876_3.json
c29f3f58_Flashcards_about_NHA_CCMA_Exam__Answer
[Question] On the horizontal axis 5 large Squares equal [Answer]
1second
[]
Flashcards about NHA CCMA Exam
Answer
http://www.studystack.com/flashcard-593521
2/1438042982745.46_20150728002302-00146-ip-10-236-191-2_721638876_3.json
c29f3f58_Flashcards_about_NHA_CCMA_Exam__Answer
[Question] Which test is used to evaluate primary Hemostasis? [Answer]
Bleeding time test
[]
Flashcards about NHA CCMA Exam
Answer
http://www.studystack.com/flashcard-593521
2/1438042982745.46_20150728002302-00146-ip-10-236-191-2_721638876_3.json
c29f3f58_Flashcards_about_NHA_CCMA_Exam__Answer
[Question] How long does is the lifespan of a platelet ? [Answer]
9-12 days
[]
Flashcards about NHA CCMA Exam
Answer
http://www.studystack.com/flashcard-593521
2/1438042982745.46_20150728002302-00146-ip-10-236-191-2_721638876_3.json
c29f3f58_Flashcards_about_NHA_CCMA_Exam__Answer
[Question] When the vaccutainer method can not be used you would use [Answer]
10-20ml syringes
[]
Flashcards about NHA CCMA Exam
Answer
http://www.studystack.com/flashcard-593521
2/1438042982745.46_20150728002302-00146-ip-10-236-191-2_721638876_3.json
c29f3f58_Flashcards_about_NHA_CCMA_Exam__Answer
[Question] Which tube must be filled completely ? [Answer]
Light blue sodium citrate tube, to maintain ration of 9:1
[]
Flashcards about NHA CCMA Exam
Answer
http://www.studystack.com/flashcard-593521
2/1438042982745.46_20150728002302-00146-ip-10-236-191-2_721638876_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] When sounds bounce back (reflect) from hard surfaces this is called an . . . [Response] ECHO [Comment]
Sound and light are both waves.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] When a ray of light is reflected from a shiny surface (e.g. a plane mirror) the angle of incidence is equal to . . . [Response] the angle of reflection. [Comment]
Angles are measured from the NORMAL.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] A line drawn at 90 degrees to a surface is called a . . . [Response] NORMAL [Comment]
Used in measuring angles of reflection and refraction.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] When rays of light change direction as they cross the boundary between two different substances this is called . . . [Response] REFRACTION [Comment]
All waves do this.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Refraction occurs when light travels between two different materials because . . . [Response] the speed of light is different in each material. [Comment]
Light slows down in glass and water compared to air.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Sound waves are . . . [Response] LONGITUDINAL waves [Comment]
Compressions and rarefactions travelling through a material ( a push-pull motion on a slinky spring)
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Light waves are . . . [Response] TRANSVERSE waves [Comment]
Like a side-to-side motion on a slinky spring.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Light waves travel at . . . [Response] the speed of LIGHT [Comment]
c = 300 000 km/s
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Sound waves travel much slower than light. Their speed in air is approximately . . . [Response] 330 m/s [Comment]
Sound travels faster in warm air than in cold.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Sound waves can be reflected and . . . [Response] REFRACTED [Comment]
When they cross the boundary between two different substances.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] If waves cross a boundary between two different substances at a right angle, there is . . . [Response] NO change of direction. [Comment]
Only speed and wavelength change.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] What changes when a light ray crosses a boundary between air and glass, travelling into the glass? [Response] Speed decreases. Wavelength decreases. It bends towards the normal. [Comment]
These are all part of REFRACTION.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] If a ray of light travels from glass into air, its speed will . . . [Response] increase. [Comment]
Light travels faster in air than glass.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Waves travelling across the surface of water are . . . [Response] transverse waves. [Comment]
The surface is displaced at a right angle to the direction of travel of the waves.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Water waves can be . . . [Response] refracted and reflected. [Comment]
Same as any other waves you care to mention.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] When water waves travel from deep water to shallow water they are refracted because . . . [Response] they travel more slowly in shallow water. [Comment]
There is more drag from the seabed.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] When a ray of light travels from glass,Perspex or water into air . . . [Response] some light is refracted and some is reflected from the boundary. [Comment]
Usually about 50% of the light is reflected.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] For light travelling from glass to air, if the angle of incidence is greater than a certain angle what happens? [Response] All of the light is reflected inside the glass. [Comment]
TOTAL INTERNAL REFLECTION. Get the spelling right!
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] What is the name of the largest angle of incidence at which light can just be refracted at a boundary between glass and air? [Response] Critical angle [Comment]
About 42 degrees for glass / air.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Light can travel along an optic fibre because of . . . [Response] total internal reflection. [Comment]
No refraction involved.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Optic fibres can be used to send telephone messages in the form of . . . [Response] pulses of light. [Comment]
Infra red lasers are used for this.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Sound waves travel through solids, liquids and gases as . . . [Response] longitudinal waves. [Comment]
Push a slinky spring away from you and back again.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] When a wave moves through a gap, or past an obstacle, it . . . [Response] spreads out from the edges. [Comment]
This is called diffraction.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Diffraction of radio waves can improve radio reception in hilly areas because . . . [Response] the waves bend over the summit and down into the valleys. [Comment]
This doesn't work with TV or microwaves because they have a shorter wavelength.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Diffraction occurs more strongly when . . . [Response] the wavelength is similar to the size of the obstacle. [Comment]
A hill of height 1000m will diffract radio waves of the same wavelength.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] When white light passes through a 60 degree prism . . . [Response] a spectrum of colours is produced. [Comment]
Isaac Newton explained this by saying that white is a mixture of all the other colours.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Different colours of light have different . . . [Response] wavelengths. [Comment]
Red has the longest, violet the shortest.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] When a spectrum is produced by a prism the effect is called . . . [Response] dispersion. [Comment]
Different colours travel at different speeds in glass - red slows down least.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Which colour is refracted most by a prism? [Response] Violet [Comment]
Violet Veers Violently
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] There are many more kinds of radiation than we can see with our eyes. The full range is called the . . . [Response] electromagnetic spectrum [Comment]
It extends to very large and very small wavelengths.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] The type of electromagnetic radiation which has the longest wavelength is . . . [Response] radio waves. [Comment]
Typically over 1 kilometre in length.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] The type of electromagnetic radiation which has the shortest wavelenth is . . . [Response] gamma rays. [Comment]
Wavelength is less than the size of an atom.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] When radiation is absorbed, the energy it carries makes . . . [Response] the substance which absorbs it hotter. [Comment]
Lying in the Sun makes me hot!
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Electromagnetic radiation may also . . . [Response] create an alternating current with the same frequency as the radiation. [Comment]
That's how a radio or TV works.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Radio waves are used to . . . [Response] transmit radio and TV programmes between different points on Earth's surface. [Comment]
Range is limited by line of sight.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Longer wavelength radio signals can be reflected from an electrically charged layer in Earth's upper atmosphere called . . . [Response] the ionosphere. [Comment]
This enables signals to be sent between distant points despite the curvature of Earth's surface
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Microwave radiation of short wavelength which can pass through Earth's atmosphere is used to . . . [Response] send information to and from satellites and within mobile phone networks. [Comment]
To receive information from a satellite you will need a satellite DISH.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] A microwave oven can be used for cooking because . . . [Response] water molecules in food strongly absorb microwaves of the correct wavelength. [Comment]
No metal objects and certainly not your hands!
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Toasters, grills and radiant heaters make use of . . . [Response] infra red radiation. [Comment]
This is emitted from warm bodies such as animals and plants.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] A TV remote control uses . . . [Response] infra red radiation. [Comment]
You might not see it yourself but try using a video camera !
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Light can be sent down optical fibres to allow doctors to see inside a patient's body. The device is called an . . . [Response] endoscope. [Comment]
It can be used at both 'ends' - but only by a qualified medical person please !
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Sunbeds make use of . . . [Response] ultraviolet radiation [Comment]
Careless exposure can result in skin cancer (melanoma) so use Factor 25 at least !
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Special coatings which absorb UV and emit visible light are used in . . . [Response] fluorescent lamps and security coding. [Comment]
Check out your white shirt at the discotheque ( yeah, I know that dates me!)
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] X-rays are used to produce shadow pictures of bones because . . . [Response] X-rays do not easily pass through bone or metal. [Comment]
It can be used at airports for screening your luggage - so leave those scissors at home.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Gamma radiation is used to . . . [Response] kill harmful bacteria in food, sterilise surgical instruments and kill cancer cells. [Comment]
Those party forks you use at barbecues have been inside a nuclear reactor you know.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Microwaves are absorbed by the water in cells which may be . . . [Response] damaged or killed by the heat released. [Comment]
So keep your hands out of the microwave and keep your mobile phone at a safe distance too.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Infra red is absorbed by the skin and felt as . . . [Response] heat. [Comment]
Nice.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Ultraviolet can pass through the skin to deeper tissues. The darker the skin . . . [Response] the more UV it absorbs and the less reaches deeper tissues. [Comment]
See, there's a reason for everything.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] X-rays and gamma rays mostly pass through soft tissues but some . . . [Response] is absorbed by the cells. [Comment]
No exposure is good exposure.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] High doses of UV, X and gamma radiation can kill normal cells. Lower doses can . . . [Response] cause normal cells to become cancerous. [Comment]
Very high doses are needed to kill cancer cells, but healthy cells are also killed. It is a high risk strategy.
[]
Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Information such as speech or music can be converted into . . . [Response] electrical signals that can be sent long distances through cables or using electromagnetic waves as carriers. [Comment]
Traditional methods: copper wires and radio signals.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Information can be converted into light or infra red signals and sent . . . [Response] along optic fibres. [Comment]
Modern methods: cheaper, less loss of energy so more efficient.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Signals which vary continuously in amplitude and/or frequency are called . . . [Response] analogue signals [Comment]
Old fashioned vinyl records and terrestrial TV ( not digital)
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Signals can be coded as a series of pulses which have two states, on or off. These are called . . . [Response] digital signals [Comment]
Now we're talking !
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] One advantage of difgital signals over older analogue signals is . . . [Response] higher quality - the signals do not change their information during the transmission process. [Comment]
Analogue signals are prone to distortion. On is on and off is still off.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] A major advantage of digital signals is . . . [Response] their information carrying capacity. [Comment]
More information can be transmitted in a given time than with analogue signals.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] As signals travel they become weaker. Random additions to the signal are called . . . [Response] NOISE [Comment]
Noise adds to both types of signal.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] With analogue signals, different frequencies may weaken to different extents. When amplified . . . [Response] the signal becomes less like the original. Its quality deteriorates. [Comment]
Noise is also amplified along with any differences.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Even though digital pulses weaken with distance, the quality is maintained because . . . [Response] noise is of low amplitude and below the level recognised as 'on'. It is treated as 'off'. [Comment]
The voltage needed for an 'on' state is much higher than the noise level.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Sounds are produced when object vibrate. The greater the amplitude of vibrations . . . [Response] the louder the sound. [Comment]
Turn it up !
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] The number of complete vibrations each second is called the . . . [Response] frequency ( measured in hertz, Hz) [Comment]
The higher the frequency of a sound the higher its PITCH
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Electronic systems can produce waves which have a frequency higher than humans can hear called . . . [Response] ultrasound or ultrasonic waves [Comment]
Above 20kHz, I give up.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Ultrasonic waves are used in medicine for . . . [Response] pre-natal scanning [Comment]
Doesn't harm the foetus like X-rays would.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] In industry, ultrasound is used for . . . [Response] cleaning delicate mechanisms and for quality control [Comment]
Can detect cracks in welds, moulded castings etc.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] The information needed for an ultrasound scan to be useful is . . . [Response] the time taken for an echo to return to the detector. [Comment]
The distance to the reflecting boundary can be calculated if the speed of sound in the material is known.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Our knowledge of the structure of the Earth comes from studying how the shock waves from earthquakes travel through it. These are called . . . [Response] seismic waves. [Comment]
Earthquake intensity is measured on the Richter scale.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Earthquakes produce waves which can be detected using . . . [Response] seismographs or seismometers. [Comment]
They produce a pen and ink trace on a rotating drum of paper.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] The outermost layer of the Earth is very thin and is called the . . . [Response] crust. [Comment]
If the Earth was the size of an apple, the crust would only be the thickness of the skin.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] The Earth's core extends about halfway to the surface. It consists of an inner and an outer core. The outer core is . . . [Response] liquid nickel and iron. [Comment]
The inner core is a solid ball of metal.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] The layer of rock surrounding the core extends almost to the surface and is called the . . . [Response] mantle [Comment]
It has the properties of a solid but it can flow very slowly.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] The overall density of the Earth is much greater than the mean densities of the rocks that form the crust. This suggests that . . . [Response] the interior of the Earth is much denser. [Comment]
Density increases with depth due to the increasing pressure of the overlying rocks.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] What are the two types of seismic waves that travel through the interior of the Earth? [Response] P and S waves. [Comment]
There are surface waves as well which only travel through the crust.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Which type of seismic waves are faster? [Response] Primary (P) waves [Comment]
They are recorded first by seismographs at the start of an earthquake.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] What is the difference between the two types of seismic waves? [Response] P waves are longitudinal, S waves are transverse. [Comment]
P waves are compression waves. S waves are shear waves.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Which type of seismic wave cannot travel in a liquid? [Response] S waves [Comment]
They need a rigid (solid) medium.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Seismic waves travel in curved paths through the interior of the Earth because . . . [Response] they are being refracted. [Comment]
They travel faster as they go deeper.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] The speed of seismic waves increases with depth because . . . [Response] the density of rock increases with depth. [Comment]
Seismic waves travel faster in denser material.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] The speed and direction of P waves change abruptly as they reach the outer core because . . . [Response] its density suddenly decreases. [Comment]
Liquids are less dense than solids.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] We know that the outer core is a liquid because . . . [Response] S waves can't travel through it. [Comment]
Only P waves can pass right through the Earth's core.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Some seismometers cannot detect the S waves from an earthquake. Why is this ? [Response] S waves can't pass through the core. [Comment]
If the seismometer is in a 'shadow zone', only P waves can reach it.
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] The fact that the edges of land masses which are separated by thousands of kilometres of ocean have shapes which fit quite closely suggests that . . . [Response] they may have been part of larger land mass which spli apart. [Comment]
e.g. south east America and west Africa
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Wegener's theory of continental drift is supported by . . . [Response] similar patterns of rocks and fossils on different continents [Comment]
Or perhaps a land bridge which broke apart could explain this
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] The upper part of Earth's mantle and crust is called the . . . [Response] lithosphere [Comment]
It is moving on top of denser material below
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] The pieces of Earth's lithosphere which are moving are called . . . [Response] tectonic plates [Comment]
Like rafts of polystyrene floating on denser water
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] The Earth's tectonic plates are moving slowly at a speed of about . . . [Response] a few centimetres a year [Comment]
We can measure this by timing radio signals
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] The process which drives plate tectonics is . . . [Response] convection currents in the mantle [Comment]
The energy is provided by radioactive decay which releases heat
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] At the boundaries between tectonic plates we find . . . [Response] more earthquakes and volcanic eruptions [Comment]
You can see a map of this in your text book
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] Where two plates meet they may slide past each other. This is known as a . . . [Response] transform fault [Comment]
They rub and produce friction e.g. California
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json
f45f88e5_Flashcards_about_Wave_Motion__Comment
[Statement] When two tectonic plates approach each other, one of them may be driven down. This is called . . . [Response] subduction [Comment]
Old crust is melted to form volcanoes
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Flashcards about Wave Motion
Comment
http://www.studystack.com/flashcard-17973
2/1438042982745.46_20150728002302-00141-ip-10-236-191-2_729415678_3.json