Details Title: Digital Media Technologies Description: Test 1 Total Flash Cards: 44 Created: 02/12/2008 08:52:14		New Users: To study from this flashcard set, or to create your own your own study flash cards, REGISTER HERE. Existing Users: CLICK HERE. Additional Film, Theatre & Television Flashcards
Cards in this set: Term electromagnetic waves (radiation) Definition Another term for light. Light waves are fluctuations of electric and magnetic fields in space. Term photon Definition The smallest (quantum) unit of light/electromagnetic energy. Photons are generally regarded as particles with zero mass and no electric charge. Term speed of light (in vacuum) Definition The speed at which electromagnetic radiation propagates in a vacuum; it is defined as 299 792 458 m/s (186,000 miles/second). Term Frequency Definition # of waves passing a given point within a specific unit of time (sec.) Term Wavelength Definition Distance between waves expressed in metric units Term How do you find Volume? Definition F x WL = V Term Amplitude Definition Power measured by the peak height of the wave. (expressed in watts) Term Attenuation Definition Loss of energy (decrease in amplitude of waveform) due to absorption by air or ground. Term Power Definition the rate at which work is done or energy is produced or consumed (Watts) Term electron Definition A negatively charged particle commonly found in the outer layers of atoms. The electron has only 0.0005 the mass of the proton. Term electron volt Definition The change of potential energy experienced by an electron moving from a place where the potential has a value of V to a place where it has a value of (V+1 volt). Term Ohm’s Law Definition Circuits have three elements: Voltage Current Resistance Term Phase Definition Relative timing of a wave cycle. Term Modulation Definition Encoding information on radio waves Term Demodulation Definition Decoding information from radio waves Term Transducer Definition Convert sound or light into RF prior to modulation Term How fast do sound waves travel through air? Definition 340 meters p/second, or 760 mph Term Multiplexing Definition Two or more different signals are placed on a single channel (FM, Color TV, etc.) Term Frequency division multiplexing (FDM) Definition Unused frequencies are used for information Term Propagation Definition Path taken by radio waves thru atmosphere Term AM radio (tower) Definition - tower is radiating element Term FM radio (tower) Definition uses antenna elements Term TV (tower) Definition attached to tower Term Polarization Definition orientation of electromagnetic waves to the surface of the earth Term AM Waves are: Definition Vertical Term FM waves are: Definition Horizantal Term TV Waves are Definition Curly Q Term Compression Definition a region where the air is compressed Term Rarefaction Definition the opposite of a compression, the air pressure is slightly lower than normal Term Steady Barometric Pressure Definition the normal air pressure of the atmosphere Term Intensity Definition the power falling on, emitted by, or passing through a specific area, measured in W/m2 Term Hearing Range is: Definition 10 octaves Term Haas Effect Definition if similar sounds arrive at the listener’s ears, the sounds that arrive first determine the perceived direction of the sound’s origin, even if the later sound is louder Term Is the human ear linear or non-linear? Definition non-linear Term TIMBRE Definition difference between sounds (tonal quality or “sound color”) Term What is an octave? Definition the distance between two notes where one has double the frequency of the other Term SOUND ENVELOPES HAVE 3 STAGES: Definition ATTACK SUSTAIN DECAY Term Phase reverse Definition corrects cancellation that can occur if two microphones are not wired correctly Term IMPEDENCE Definition Measurement of the resistance presented to the flow of electrical signal voltage Term Hi Z has (greater,lesser) output level Definition greater Term Low Z has (greater, lesser) output level Definition lesser Term High Pass FIlter: Definition attenuates all frequencies below a certain point Term Low Pass Filter Definition attenuates all frequencies above a certain point Term Notch Definition Used to cut out an extremely narrow bandwidth