Year 10 Edexcel Physics Exam: Waves + EM Spectrum

Year 10 Edexcel Physics Exam: Waves + EM Spectrum

1. Waves

   • Transfer energy and info
   • Transverse
     • Sideways vibrations
   • Longitudinal
     • Parallel vibrations
   • Use Oscilloscope to measure speed of sound
   • Measure speed of water ripples by strobe ligts
   • To find speed of waves in solids use peak frequency
   • At boundaries, they are absorbed, transmitted or reflected
   • Refraction, waves changing direction at boundary
   • Sound
     • Caused by vibrating objects
     • Ultrasound
       • Freq higher than 20 000 Hz
       • Ultrasound partially reflected at boundaries
       • Medical Imagery
       • Industrial imagery
     • Infrared
       • Freq lower then 20 Hz
       • Seismic waves
         • P-waves and S-Waves
           • P-waves can travel through the earth
           • S-waves cant travel through the earth

2. Reflection

   • angle of incidence = angle of refolection
   • Total Internal Reflection depends on critical angle
   • can be specular or diffuse
   • exp on p.329

3. Visible light and colour

   • colour and transparency depend on absorbed wave lengths
   • colour filters transmit certain wavelengths

4. Lens

   • Converging and vDiverging
     • converging bulges outwards
     • diverging caves inwards
   • bigger curvature bigger power

5. EM

   • There is a continuous spectrum of EM waves
   • Radio, Micro, Infra Red, Visible, Ultra, X-rays
   • different em waves have different pro[perties
   • Every object absorbs and emits Em radiation
     • Radiation affects earths temp
   • Radio waves made by oscillating charges
   • Radio waves used mainly for communicaTIONS AND BROADCASTING