atom {sci 7 3rdq}

• Atom


  Smallest unit of matter
• Nucleus


  Center part of the atom
• Three atomic particles


  • Proton
  • Neutron
  • Electron
• Proton


  Positive charge, discovered by Ernest Rutherford in 1920
• Neutron


  Uncharged particles, discovered by James Chadwick in 1932
• Electron


  Negative charge, discovered by Joseph John Thomson in 1897, known as corpuscles
• The nucleus contains protons and neutrons
• The nucleus of an atom contains protons and neutrons.
• ROYGBIV


  Acronym for red, orange, yellow, green, blue, indigo, violet
• Dispersion


  Phenomenon in which a prism separates white light into its component colors
• Light


  • Travels in a straight line
  • In the form of transverse waves
• Prism


  A transparent, refracting device bounded by five plane surfaces inclined at some angles
• Rainbow


  A spectac6display of colors
• Speed of light equals 300,000,000m/s
• Visible light


  Light people can see
• The light that is reflected by an object


  Determines its color
• Objects are visible because of the light they reflect
• Amplitude


  Measurement of the amount of energy transferred by a wave
• Highest surface part of a wave

  Crest
• Wavelength


  The distance between one crest to another
• Wave components


  • Origin - the original position of the medium
  • Wavelength - the distance between one crest to another
  • Trough - lowest point the wave
  • Amplitude - the distance from the line of origin to crest or trough of the wave
• Transverse wave


  • Going in one direction
• Longitudinal wave


  • Not one direction
• Mechanical waves


  • Require a medium, can only travel through matter
• Matter


  • Solid
  • Liquid
  • Gas
• Types of waves


  • Electromagnetic
  • Mechanical
• Electromagnetic waves


  Require electricity
• Mechanical waves


  Travel through matter (solid, liquid, gas)
• Wave


  A disturbance that transfers energy from one place to another
• Charging by friction


  Use of different objects that you have to rub
• Charging by contact


  Use of different objects you need to hold (having contact)
• Charging by friction - combing hair

  1. Before brushing hair comb (neutral)

  2. Hair (neutral)

  3. After brushing hair - both are oppositely charged

  4. Comb (negative)

  5. Hair (positive)
• Charging by induction


  No need to touch, rub, or hold
• discovered atom is john dalton