topic p6- waves

• what is a wave?

  a disturbance that transfers energy without transferring matter
• what are the two main types of waves?

  transverse and longitudinal
• what is a transverse wave?

  a wave where particles move perpendicular to the wave direction (e.g., light)
• what is a longitudinal wave?

  a wave where particles move parallel to the wave direction (e.g., sound)
• what is amplitude?

  the maximum displacement from the rest position
• what is wavelength?

  the distance between two crests or troughs
• what is frequency?

  the number of waves per second (Hz)
• what is the wave speed formula?

  wave speed= frequency X wavelength
• what is the unit of wave speed?

  metres per second (m/s)
• what is the difference between frequency and period?

  frequency is waves per second; period is the time taken for one wave ( period= 1/ frequency)
• what is refraction?

  the bending of waves as they pass between different media
• what is the electromagnetic spectrum?

  the range of all electromagnetic radiation
• list the types of electromagnetic waves in order

  • radio waves
  • microwaves
  • infrared
  • visible light
  • ultraviolet
  • x-rays
  • gamma rays
• what is the speed of light in a vacuum?

  3 X 10 ^8 m/s
• what are the properties of electromagnetic waves?

  transverse, travel through a vacuum, and travel at the speed of light
• what are microwaves used for?

  cooking and communication (satellite, phones)
• what is infrared radiation used for?

  night vision, remote controls, heat detection
• what is ultraviolet radiation used for?

  sterilization, black lights, counterfeit detection
• what are x-rays used for?

  medical imaging and object inspection
• what are gamma rays used for?

  cancer treatment and sterilizing medical equipment
• what is the relationship between wavelength and frequency?

  as wavelength decreases, frequency increases (inverse relationship)
• what are seismic waves?

  waves that travel through the earth, used to study its structure
• difference between p- waves and s-waves?

  p-waves are longitudinal and can travel through solids and liquids; s-waves are transverse and only travel through solids
• what is ultrasound?

  high-frequency sound waves used in medical imaging and industrial applications
• how do radio waves work in communication?

  radio waves carry signals for communication, e.g., in phones or radio broadcasts
• how can infrared radiation be investigated?

  using thermograms or infrared cameras to detect heat
• what are the dangers of electromagnetic waves?

  high-frequency waves (UV, x-rays, gamma) can damage cells and increase cancer risk
• how are waves reflected, absorbed and transmitted?

  waves reflect off surfaces, are absorbed (converted to heat), or pass through material (transmitted)
• how can waves be investigated experimentally?

  use a ripple tank to study waves (observe reflection, fraction, and diffraction) or stretch a slinky to study transverse and longitudinal waves

  measure speed with: speed= distance/ time