Waves Flashcards
What do waves transfer?
Energy
What is the definition of a transverse wave?
A wave in which the particles of the medium vibrate at right angles to the direction the wave is travelling in.
What is the definition of a longitudinal wave?
a wave in which the particles of the medium vibrate parallel to the direction the wave is travelling in.
Give me an example of a longitudinal wave
sound waves
Give me an example of a transverse wave
water waves and electromagnetic radiation waves
How do you measure the wavelength of a longitudinal wave?
From compression to compression
How do you measure the wavelength of a transverse wave?
Measure from one point on one wave to the same point on another
what do you call it when a longitudinal waves particles are spread out ?
Rarefaction
How do you find the amplitude of a wave?
Measure from the middle to the bottom or top of the wave
What is the top of a transverse wave called?
Crest
What is the bottom of a transverse wave called?
Trough
What is diffraction?
Diffraction is when waves bend around corners.
Compare long wave and short wave diffraction
The longer the wavelength the greater the diffraction. i.e long wavelengths diffract better than short wave lengths
describe the diffraction when the gap is the same size or smaller than the wavelength
Semi-circular waves are formed on the other side of the gap. i.e there is much more spreading
Describe the diffraction when the gap is larger than the wavelength
Little spreading will happen
What way in the E-m spectrum does the frequency go from low to high?
Radio (Low Frequency) to Gamma (High Frequency)
What way in the E-m spectrum does the wavelength go from small to large?
Gamma rays ( small wavelength 10^-13m ) to Radio waves ( Large wavelength 10 m )
What type of wave is the waves on the e-m spectrum?
All are Transverse
What speed does the e-m spectrum waves travel at
Speed of Light ( 3x10^8 m/s)
What is a source , detector and use for Radio waves?
A Source is lightning or broadcast radio towers , A detector of Radiowaves is an aerial or antenna and A use for radiowaves is communication
What is a source, detector and use for Microwaves?
A source is the sun and a radar , A detector of microwaves is an aerial and a use for microwaves is mobile phone signals
What is a source , detector and use for Infrared?
A source is the sun , a detector of Infrared radiation is a photodiode or a Closed circuit device (CCD) and a use for Infrared is a tv remote
What is a source , detector and use for Visible light?
A source for visible light is the Sun , a detector of visible light is Photofilm,the retina of the eye or a CCD and a use for visible light is to predict the weather
What is a source , detector and use for Ultra violet light?
A source is the sun and tanning beds , a detector of Ultra violet light is fluorescent dye and a use for ultra violet light is bank note security and sterilise medical equipment
What is a source, detector and use for X-Rays?
A source of x-rays are radon gas and cosmic rays , a detector of X-Rays is photofilm and a use for x-rays is to take an image/picture of a broken bone
What is a source, detector and use for gamma rays?
A source is nuclear explosions and lightning , a detector or gamma rays is Photofilm of Geiger-Muller tube (GM Tube) and a use for gamma rays is radiotherapy
IS it correct to say that the energy associated with the different forms of e-m Radiation is in direct proportion to the frequency?
Yes that is correct
When does refraction occur?
Refraction occurs when light passes from one medium into another.
How does the speed of the wave change during refraction?
when the light moves into a denser medium than it was in the speed of the wave slows down. So when the light wave moves from glass into air the speed of the light increases
How does the wave change direction during refraction?
when moving from air to glass the light changes direction slightly towards the normal
when moving from glass to air the light changes direction slightly away from the normal
What is the “Normal” ?
The Normal is an imaginary line drawn perpendicular to the boundary between the two materials
What is the “Angle of Incidence”?
The angle of incidence is the angle between the Incident ray (Before it is refracted i.e before it changes medium) and the normal
What is the “Angle of Refraction”?
The Angle of Refraction is the angle between the refracted ray ( after the change of medium) and the normal
How do you identify the Angle of Incidence in diagrams?
The angle of Incidence is the angle before the change in medium
How do you identify the angle of refraction in diagrams?
The angle of refraction is the angle after the change in medium
How do you identify the “Normal” in diagrams?
The line that is perpendicular to the refraction
