rtvf quiz 2

  1. center of the nucleus with an electrical charge
  2. protons
    in the nucleus with a positive charge
  3. electrons
    circle the nucleus with a negative charge
  4. most elements have a ___ charge
  5. in ____, electrons can be easily dislodged from their orbits and attract to other atoms
  6. electricity
    flow of electrons
  7. direct current
    an electrical circuit through which the flow of electrons moves only in one direction, electrons have to loop to connect bulb and battery
  8. most video equipment 
    direct current
  9. interrupts the flow of electrons
  10. alternating current
    flow of electrons change direction constantly, negative to positive to negative
  11. efficient for transmission through wires over long distances, household electricity
    alternating current
  12. the pressure of the electricity 
    voltage, measured in volts
  13. voltage: ____ is constant
    speed is constant, pressure is not
  14. the volume of electrons, number of electrons passing a certain point in a given time
    current, measured in amps
  15. determined by voltage and current, measurement of work accomplished 
    power, measure in watts. 
  16. watts=
    volts x amps
  17. property of a material to resist the flow of electrons through when voltage is applied
    resistance, measured in ohms
  18. electricity in television
    frequency, AC frequency, Impedance
  19. action that repeats itself, an electrical circuit that puts out repeated and equal bursts of energy
    frequency, 100 bursts a second has a frequency of 100 Hz
  20. AC Frequency
    if the electricity in your home is 120 V AC, the electricity will go from 0V to 120V, back down to O then to -120V then up to 0...one cycle. household has 60 times a second=60Hz=120 V 60 Hz AC
  21. impedance
    the combination of resistance, capacitance, and inductance. helps to tell the crew if 2 or more circuits will interact well. 
  22. if amp has an impedance of 8 ohms then you need to hook up speakers with ___resistance
    8 ohm
  23. fields (induction)
    any electrical circuit that has a changing flow of electrons will create an electromagnetic field around itself
  24. a high-tension power line running cross country has an extremely ___ electromagnetic field
  25. signal-to-noise ratio
    the relationship between the strength of the signal and the amount of noise the circuitry creates, dB, logarithmic ratio
  26. kilo
    K 1,000
  27. Mega
    M 1,000,000
  28. Giga
    G 1,000,000,000
  29. milli
    m 1/1,000
  30. micro
    u 1/1,000,000
  31. nano
    n 1/1,000,000,000
  32. average ear hears sounds between
    20 Hz and 15,000 Hz
  33. early technology allowed recordings of up to _____ until late 1940s
    5,000 Hz
  34. HDTV standard accepted is 
    5.1 surround sound stereo standard
  35. five main speakers used in 5.1 surround sound stereo 
    left front, center front, right front, right surround and left surround and subwoofer
  36. subwoofer
    the .1 for very low sounds that can be placed anywhere in surround sound
  37. consumer video is ____ impedance
    high, 10,000 ohms
  38. consumer audio is ______
    unbalanced, uses 2 wires to carry message and does not resist induced noise
  39. balanced audio systems
    uses 3 wires to carry message and resist induced noise
  40. 3 wires of balanced audio system
    one is ground, two carry the same signal ("in phase") but noise is likely to hit the 2 wires at different times ("out of phase"). equipment getting the signal will let things in phase pass but filter out "out of phase" noise. both lines of the system must be balanced.
  41. mics create own ____ and have very ___ signals
    electricity, weak. 40 to 60 dB lower than line.
  42. to record natural sound, first step is 
    a microphone
  43. microphones
    transducer that changes sound into electrical energy. all have highly flexible diaphragm that vibrate with sound movements in air to create a very small electrical voltage that passes on to next piece of equipment in system
  44. "digital" mics
    will have an A to D converter attached to diaphragm circuitry to create the digital signal-requires electrical circuitry and power. large and bulky. 
  45. mixer
    brings several sound sources together, measure their strength and hear them. wont hear them unless they go through mixer
  46. difference between analog and digital mixers
    analog only deals with analog sound. digital deals with both and have built in A to D converters and are more expensive
  47. loudspeakers
    analog transducer that converts electrical energy into sound energy
  48. how loudspeakers work 
    has small piston wrapped in coil of fine wire mounted inside a magnetic field, piston is attached to a flexible cone, the coil creates a changing electromagnetic field that interacts with surrounding magnetic field causing piston to move back and forth. makes sound.
  49. for digital video, we use ____ sampling rates and ___ processing levels
    high sampling rates (in megahertz), low processing levels (8- or 10- bit processing)
  50. for digital audio, we use ___ sampling rates and very ___ processing
    low sampling rates (48,000 Hz on digital videotape) and very high processing (16 bit)
  51. audio compression
    done by dividing the frequency range into different bonds of frequencies and compressing them separately  
  52. recording process
    sound will enter the recorder from the mic and will enter an A to D converter where it is put down on recording medium as series of 0s and 1s. when played back it goes through a D to A converter
  53. uncompressed vs compressed
    uncompressed is better than compressed
  54. digital audiotape recorder
    DAT: uses a rotating head wheel that moves opposite of tape, somewhat delicate and easy to break, downloading the info to a computer takes real time
  55. Digital Audio Workstations
    DAW: high budget productions, send audio in the form of a computer file to a professional sound company for editing, processing, adding of sound effects 
Card Set
rtvf quiz 2