Topic 6 - Waves

• What is the wavelength of a wave?

  the distance between two of the same points on a wave
• What is the amplitude of a wave?

  The maximum displacement from the equilibrium position.
• What is a time period?


  The time taken for one complete oscillation
• what is the formula for frequency?


  f = 1/T
• What's the formula for wave speed?

  wave speed = frequency x wavelength
• Describe a transverse wave


  A transverse wave is where the oscillations are perpendicular to the direction of energy transfer.
• Describe a longitudinal wave


  A longitudinal wave is where the oscillations are parallel to the direction of energy transfer.
• What can happens to waves

  waves can be absorbed, transmitted and reflected.
• What is the equation for ray diagrams

  angle of incidence = angle of reflection.
• What is the normal in ray diagrams


  vertical line between the incident ray and the reflected ray. 90 degrees to the boundary.

  
• What is specular reflection?


  Reflection from a smooth surface in a single direction.
• What is diffuse reflection?


  When a wave is reflected by a rough surface & the reflected rays are scattered in lots of different directions.
• what does a high density in a wave mean

  slower wave.
• What does refraction mean?

  The bending of rays of light as they pass from one medium into another, from air to water, or from air to glass.
• Light travelling from a less dense material, into a more dense material, will bend ________ the normal.

  towards
• What's the electromagnetic spectrum?

  (shorter wavelength, higher frequency, higher energy) gamma rays, x rays, UV, visible, infrared, microwave, radio.

  
• electromagnetic waves are what type?

  transverse waves.
• what speed do waves travel at in a vacuum?

  3x10 8 m/s
• what waves can be used for communication

  radio waves, microwaves
• what electromagnetic waves are ionizing

  gamma rays, x-rays
• what was oscilloscopes used for?


  Display the wave frequency of an alternating current
• what are the three types of radio waves?

  Long wave

  Short wave

  Very short wave
• What are micro waves used for?

  communication and cooking food
• What are infrared waves used for?

  electrical heaters, cooking food, infrared cameras
• What are ultraviolet waves used for?

  Energy efficient light bulbs, security marking, sunbeds
• What are visible light rays used for?

  photography
• How are X-rays used?

  medical imaging
• What are gamma rays used for?

  Sterilizing food and medical equipment
• are gamma rays and xrays harmful

  yes they damage our cells in the body.