P6

• What do waves transfer through a medium?

  Energy
• What is frequency in wave terms?

  Number of complete waves per second
• What does the period of a wave measure?

  Time for a complete wave to pass
• How do sound waves affect air particles?

  They move away, but particles don't
• What is amplitude in wave terms?

  Maximum displacement from rest position
• What is wavelength?

  Length of a full cycle of a wave
• What happens when a wave hits a boundary?

  It can be absorbed, transmitted, or reflected
• What are the differences between transverse and longitudinal waves?

  • Transverse Waves:
  • Oscillations perpendicular to energy transfer
  • Examples: Ripples in water, electromagnetic waves, waves on a string
  • Longitudinal Waves:
  • Oscillations parallel to energy transfer
  • Examples: Sound waves, P-waves
• What is wave speed?

  Speed at which a wave transfers energy
• What is 1 Hz in wave terms?

  1 wave per second
• What is the formula for wave speed?

  $v =$$f \times \lambda$
• How is the speed of sound measured?

  Using microphones and an oscilloscope
• What does the angle of incidence equal?

  Angle of reflection
• What are the types of reflection?

  • Diffuse Reflection:
  • Surface appears matte
  • Reflected rays scatter in all directions
  • Specular Reflection:
  • Surface gives clear reflection
  • Reflected rays travel in one direction
• What is refraction?

  Change of direction when crossing a boundary
• What happens to wavelength during refraction?

  It decreases when wave slows down
• What is the electromagnetic spectrum?

  Continuous range of electromagnetic waves
• What are the properties of electromagnetic waves?

  • They are transverse waves.
  • Transfer energy from source to absorber.
  • Travel at the same speed in air or vacuum.
• What creates gamma rays?

  Changes in an atom's nucleus
• What are the uses of electromagnetic waves?

  • Radio waves: TV, radio communications
  • Microwaves: Cooking, satellite
  • Infrared: Electric heaters, cameras
  • Visible light: Energy-efficient lights
  • UV: Sun tan beds, medical treatments
  • X-rays: Medical imaging
  • Gamma rays: Cancer treatment
• What is radiation dose?

  Measure of risk from radiation exposure
• What factors affect radiation risk?

  Size of dose and type of radiation
• What are harmful effects of ionizing radiation?

  Can cause skin cancer and gene mutation
• What are the characteristics of real and virtual images?

  • Real Image:
  • Formed when light rays converge
  • Can be projected on a screen
  • Virtual Image:
  • Formed when light rays appear to diverge
  • Cannot be projected on a screen
• What type of images do convex lenses produce?

  Real or virtual images
• What type of images do concave lenses produce?

  Always virtual images
• What is the principal focus of a lens?

  Point where parallel rays converge
• How do magnifying glasses work?

  Use convex lenses to create virtual images
• What happens to the image height in magnification?

  Larger image height means larger magnification
• What are the four ray diagrams for convex lenses?

  1. Object beyond 2F: Real, inverted, smaller
  2. At 2F: Real, inverted, same size
  3. Between 2F and F: Real, inverted, bigger
  4. Nearer than F: Virtual, upright, bigger
• What is the ray diagram for concave lenses?

  • Always produces a virtual image
  • Upright and smaller than the object
• What determines the color of an object?

  Wavelengths of light that are reflected
• What is white light made of?

  All colors of visible light
• What do opaque objects do with light?

  Do not transmit light
• What do black objects do with visible light?

  Absorb all wavelengths of visible light
• What do white objects do with visible light?

  Reflect all wavelengths equally
• What do color filters do?

  • Transmit certain colors (wavelengths)
  • Absorb the rest
• How does temperature affect infrared radiation emission?

  Higher temperature means more IR radiation emitted
• What is a perfect black body?

  Absorbs all radiation that hits it
• What happens to intensity as an object gets hotter?

  Intensity of emitted wavelengths increases