Tricky Physics

• Nuclear fission


  The process in which an unstable heavy atomic nucleus splits into two or more lighter nuclei often called fission fragments with energy being released
• Chain reaction in nuclear fission

  1. Neutron hits nucleus

  2. Nucleus splits

  3. Releases neutrons

  4. Neutrons hit other nuclei

  5. Causing more fission reactions
• Gamma ray


  An electromagnetic wave of very high frequency and energy
• Ionization


  The addition or removal of an electron from a neutral atom, resulting in a positive or negative ion
• Absorbed dose


  The energy absorbed by a material per unit mass
• Equivalent dose


  The absorbed dose multiplied by the radiation weighting factor
• Equivalent dose rate


  The equivalent dose per unit time
• Nuclear fission


  The process in which an unstable heavy atomic nucleus splits into two or more lighter nuclei called fission fragments, with energy being released
• Nuclear fusion


  The process of small nuclei joining together to form a larger nucleus, with energy being released
• Light year


  The distance traveled by light in one year (a distance, not a time)
• Big Bang Theory

  The universe started as an infinitely hot, infinitely dense single point of matter called a singularity, and rapidly expanded and cooled over time
• The age of the universe is roughly 13.8 billion years old
• Detectors for different types of electromagnetic radiation

  • Radio/TV waves: aerial
  • Microwaves: aerial
  • Infrared: photodiode
  • Visible light: retina of eye
  • Ultraviolet: fluorescent chemicals
  • X-rays: photographic film
  • Gamma rays: Geiger-Muller tube
• Continuous spectrum


  Full spectrum of colors from red to violet, produced by passing white light through a prism
• Line absorption spectrum


  Continuous spectrum with certain wavelengths removed, appearing as dark bands
• Line emission spectrum


  Black background with specific colored lines corresponding to different wavelengths
• Newton's Second Law


  If a mass has an unbalanced force acting on it, it will accelerate in the direction of that force (F = ma)
• Newton's Third Law


  For every action, there is an equal and opposite reaction