PHYSICS: Waves

• What is one way in which energy may be transferred between stores?

  Waves
• What types of waves transfer energy but not matter?

  Mechanical and electromagnetic waves
• What is the definition of a medium in the context of waves?

  A material through which a wave can be transmitted
• How do sound waves affect air particles?

  They cause air particles to vibrate back and forth
• What is the difference between longitudinal and transverse waves?

  Longitudinal waves have vibrations parallel to wave travel, while transverse waves have vibrations at right angles
• What do mechanical waves cause in a medium?

  Oscillations of particles
• What do electromagnetic waves cause?

  Oscillations in electrical and magnetic fields
• What is the definition of matter?

  Sub-atomic particles and anything made from them, such as atoms and molecules
• What are the key terms used to describe parts of a wave?

  • Rest position: undisturbed position of particles
  • Displacement: distance moved from rest position
  • Peak: highest point above rest position
  • Trough: lowest point below rest position
  • Amplitude: maximum displacement from rest position
  • Wavelength: distance covered by a full cycle
  • Time period: time for a full cycle
  • Frequency: number of waves passing a point each second
• How is wavelength measured?

  From peak to peak or trough to trough
• What is the time period of a wave?

  The time taken for a full cycle of the wave
• How is frequency defined in the context of waves?

  The number of waves passing a point each second
• How do the definitions of amplitude and displacement differ?

  Amplitude is the maximum displacement, while displacement is the distance moved from rest position
• If a wave has a frequency of 5 Hz, how many waves pass a point in one second?

  5 waves
• If a wave has a wavelength of 2 m and a frequency of 3 Hz, what is its speed?

  v = 6
• What are the characteristics of mechanical and electromagnetic waves?

  Mechanical Waves:

  • Require a medium to travel
  • Cause oscillations in particles

  
  

  Electromagnetic Waves:

  • Do not require a medium
  • Cause oscillations in electrical and magnetic fields
• What is one way in which energy may be transferred between stores?

  Waves
• What types of waves transfer energy but not matter?

  Mechanical and electromagnetic waves
• What is the equation to calculate the time period of a wave?

  1 / f
• If the frequency of a wave is 50 Hz, what is its time period?

  $T =$$0.02~s$
• How is the time period (T) measured?

  In seconds (s)
• How is frequency (f) measured?

  In hertz (Hz)
• What is the formula to calculate wave speed?

  wave speed = frequency × wavelength

  v = fλ
• What is the wave speed of a wave with a frequency of 50 Hz and a wavelength of 6 m?

  $v =$$300~m/s$
• How is wave speed (v) measured?

  In metres per second (m/s)
• How is wavelength (λ) measured?

  In metres (m)
• What is the speed of a wave with a frequency of 0.2 Hz and a wavelength of 25 m?

  $v =$$5~m/s$
• What are the key components of wave calculations?

  • Time period: T = 1 / f
  • Wave speed: v = λ f
  • Frequency: measured in Hz
  • Wavelength: measured in meters
• What is one way in which energy may be transferred between stores?

  Waves
• What do both mechanical and electromagnetic waves transfer?

  Energy but not matter
• What is the composition of air in relation to sound?

  • Air is made up of tiny particles
  • Sound is created when these particles vibrate and collide
  • Vibrations pass between air particles to transmit sound
• How does sound reach a person's ear?

  Through the vibration of air particles that vibrate the ear drum
• How does the speed of light compare to the speed of sound in air?

  Light travels much faster than sound
• If a person fires a starting pistol and raises their hand simultaneously, what can an observer do?

  Record the time difference between seeing the action and hearing the sound
• What is the formula to calculate the speed of sound?

  Speed = distance / time
• How is speed denoted in the speed formula?

  As (v)
• What unit is speed measured in?

  Metres per second (m/s)
• What unit is distance measured in?

  Metres (m)
• What unit is time measured in?

  Seconds (s)
• If an observer records a 1.2 s time difference and is 400 m away, what is the speed of sound calculated?

  $v =$$\frac{400}{1.2} =$$333~m/s$