waves

waves

1. x-rays

   • used in hospitals

2. infa red

   • night vision

3. gamma

   • killing bacteria in food

4. ultra-violet

   • used to detect forgeries

5. visible light

6. microwaves

   • cooking food

7. radio waves

   • television and radio

8. electromagnetic spectrum

9. sound waves

   • must travel through matter
     • cant travel through vacuum
   • vibrations in air
     • transverse waves

10. charisteristics of waves

    • waves are vibrations stored in them is energy
      • transverse waves are waves that travel at right angles to the direction of travel
        • longitudinal waves are when the direction of the waves is the sames as the direction of travel
    • example of a wave is when you throw a pebble into water the energy from the pebble is being transfered to the wave.
      • energy makes the water vibrate up and down
    • waves on a graph
      • amplitude is the height from the mid point to the crest
      • frequency is the number of waves produced each second
      • wavelength is the distance between the crests measured in hertz
    • calculations for waves
      • speed(mps) = frequency(hertz) * wavelength(meters)
        • frequency(hertz) = speed(mps) / wavelenght(meters)
          • wavelength(meters) = speed(mps) / frequency (hertz)
    • 3 basic things waves do
      • refract
      • defract
      • reflect