Test 1 Short Answer

• What type of waves travel through matter and involves the motion of the particles of the matter they pass through?


  Mechanical
• What type of wave has individual particles moving perpendicular to the direction of the wave?

  Transverse
• What type of wave has regions of compression and rarefaction along the direction of motion?

  Longitudinal
• What is the name for the phenomenon where constructive and destructive interference cause sound to be alternatively loud and soft?

  Beating
• What is the name of the scale that is used to measure sound intensity?


  Decibel scale
• In a science fiction movie, someone screams in space because they didn't put on a space suit. What's wrong where?


  Sound waves need a medium to travel in
• Calculate the wavelength of sound at 20 Hz in 30 degrees C air?


  17
• What is the name for the type of oscillatory motion for a system where the net force can be described by Hooke's Law?


  Simple Harmonic Motion
• What is defined as the condition in which the damping of an oscillator results in it returning as quickly as possible to its equilibrium condition?


  Critical damping
• What is the name of the frequency as which a system would oscillate if there were no driving or damping force?


  Natural frequency
• What type of frequencies produce standing waves?


  Resonant frequencies
• What is the name of the perceived frequency shift that an observer hears as a source moves towards or away from here?


  Doppler effect
• Perception of sound frequencies?


  Pitch
• Sounds below 20Hz?


  Infrasound
• Sounds above 20,000 Hz?


  Ultrasound
• SI unit of charge?


  Coulumb
• Like charges _____, opposites ____?

  repel, attract
• What is the name for any substance that has free electrons and allows these free electrons to move freely through it?


  Conductor
• What is the name for any substance that doesn't allow free electrons to move throughout it?


  Insulator
• Why can field lines never cross?


  The force on the charge would point in 2 directions at once
• When excess charge is placed on a conductor or the conductor is put into a static electric field, charges in the conductor quickly respond to reach a steady state. What is the name of this state?

  Electrostatic equilibrium
• What direction (relative to the surface) do the field lines due to positive excess charge on a conductor look like?


  Perpendicular to the surface and point away from the surface
• Where does the excess charge reside on a conductor?


  On the surface