Grade Ten Science Review

• Light


  An electromagnetic wave
• Electromagnetic waves


  • Do not require a medium for transmission
  • Energy is transferred through radiation
• Medium


  A physical substance through which energy can be transferred
• Radiation


  A method of energy transmission that does not require a medium
• Wavelength


  The distance from one crest to the next
• Electromagnetic waves carry both electric and magnetic parts
• In a vacuum the wave travels at the speed of light, 3.00 * 10 ^ 8 m / s
• Electromagnetic wave types


  • Radio waves
  • Microwaves
  • Visible light
  • X-rays
  • Gamma rays
• Classification of waves


  Classification of ways by their energy levels
• Visible light is a small range of the entire spectrum
• Visible light


  Electromagnetic waves that the human eye detects
• Colors of visible light

  • Red
  • Orange
  • Yellow
  • Green
  • Blue
  • Indigo
  • Violet
• White light


  Made up of all the colors of light in the visible spectrum
• Light production


  1. Atoms within a material absorb some form of energy

  2. Electrons become excited and jump to a higher energy level

  3. When the electron returns to the original energy level they release energy in the form of a photon (light)
• Sources of light


  • Sun
  • Incandescence
  • Electric discharge
  • Fluorescence
  • Phosphorescence
  • Chemiluminescence
  • Bioluminescence
  • Triboluminescence
  • LED lights
• Incandescence


  When materials such as metals are heated to a high temperature they begin to glow, starting red and transitioning to orange, yellow, white, and then bluish white
• Electric discharge


  When an electrical current passes through a gas, light is produced
• Phosphorescence


  Phosphorus absorb light at a high energy and release visible light at a lower energy
• Fluorescence


  When an object absorbs ultraviolet light and immediately releases the energy as visible light
• Chemiluminescence


  A chemical reaction can result in the production of light/energy, typically with no heat produced
• Bioluminescence


  Chemiluminescence occurring in a living organism
• Triboluminescence


  When certain types of crystals are scraped or banged together, sparks are produced
• Light emitting diodes (LEDs)


  A type of electrical switch made from semiconductor materials such as silicon, that only flow in one direction
• Light travels in a straight line
• Incident light


  Light emitted from a source
• Virtual image


  An image formed by light coming from an apparent light source, where the image is formed by rays that do not come from the location of the image
• Concave mirror


  Reflection is from the inner surface of the spherical section
• Convex mirror


  Reflection is from the outer surface of the spherical section
• Physical change


  Reversible change that does not create a new substance
• Chemical change


  Irreversible change that creates at least one new substance
• Physical property


  Something that can be observed without a new object forming
• Qualitative property


  Physical property that involves the five senses
• Quantitative property


  Physical property that involves numbers
• Chemical property


  Description of how two substances interact
• Diatomic elements


  Two of the same elements combined
• Proton


  Positively charged and in the nucleus
• Neutron


  Neutral and in the nucleus
• Electron


  Negative in the orbit
• In an atom the number of protons and neutrons are the same
• All atoms want to become stable