Properties of waves

• Waves can be transverse (perpendicular to direction of travel) or longitudinal (parallel to direction of travel).
• Define amplitude


  The amplitude of any wave is the maximum distance a point moves from its rest position. The amplitude of a transverse wave is the height of a peak or trough from the waves rest position.

  The larger the amplitude, the greater the energy of the wave
• Define wavelength


  The wavelength of any wave is the distance between two matching points on neighbouring waves. The wavelength is the same whichever two matching points are used to measure this distance.

  The symbol used to represent wavelengths is LAMDA SIGN
• Frequency


  The frequency is the number if waves passing any point each second

  frequency = number of waves past a point/time

  frequency is measures in hertz (Hz)

  1 wave per second = 1 Hz
• longitudinal wave


  The wavelength of any wave is the distance between two matching points on neighbouring waves. The wavelength is the same whichever two matching points are used to measure the distance
• Do waves transfer energy and information without transferring matter?

  YES
• Whats the formula between speed frequency and wave length

  speed = frequency x wavelength
• Whats the relationship between frequency and time period 


  frequency = 1/time period
• Can all waves be reflected and refracted?

  YES
• Light is part of a continuous electromagnetic spectrum that includes radio, microwave , infrared, visible light, ultra violet, x-rays and gamma ray radiations and that all these waves travel at the same speed in free space
• The order if the electromagnetic spectrum is in terms of decreasing wavelength and increasing frequency, including the colours of the visible spectrum
• What are some uses of radiowaves

  broadcasting and comms
• What are some of the uses of microwaves

  cooking and satellite transmissions
• What are some of the uses of infrared

  heaters and nightvision equipment
• What are some of the uses of visible light

  optical fibres and photography
• What are some of the uses of ultraviolet

  fluorescent lamps
• What are some of the uses of X-Rays

  observing the internal structure of objects and materials, including for medical applications
• What are some of the uses for gamma rays

  sterilising food and medical equipment
• What are the effects of excessive exposure to the human body of microwaves What are the effects of excessive exposure to the human body of infrared and how can it be avoided?

  internal heating of body tissue

  Keeping a safe distance away from the microwave
• What are the effects of excessive exposure to the human body of ultraviolet and how can it be avoided?

  damage to surface cells and blindness

  wearing hats to shade the face and wear sunglasses to protect eyes
• What are the effects of excessive exposure to the human body of gamma raysand how can it be avoided?

  cancer, mutation

  Using a concrete wall between you and the ray
• What are the effects of excessive exposure to the human body of infrared and how can it be avoided?

  Effects: Burns, skin damage, eye damage. Avoidance: Limit exposure, use protective clothing, use barriers like glass.
• Soundwaves are longitudinal waves which can be reflected and refracted