BY: Kimberly Fraser and Brittany Burr

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• BY Kimberly Fraser and Brittany Burr

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Questions!!!

• Q Name a fundamental force
• A Gravity, Electromagnetic, Weak, Strong
  Nuclear
  
• Q Name some forces that are not Fundamental
  Forces.
  
• A Tension Force, Normal Force, Frictional Force,
  Centripetal Force etc.

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Key Terms to Know and Understand

• Photon- a tiny particle or bundle of
  electromagnetic radiation
  
• Nucleus-the central part of an atom that includes
  nearly all of the atomic mass and consists of
  protons and usually neutrons
  
• Electron-an elementary particle that has a
  negative charge of electricity and travels around
  the nucleus of an atom
  
• Charge-a quantity of electricity

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Gravity Facts
Gravity is the tendency of objects of mass to
accelerate towards each other.
It is the weakest of the four fundamental
forces, but acts over great distances and is
always attractive. The stars and planets exist a
nd function the way they do, staying in orbit,
due to gravity.
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GRAVITY
The gravitational force on earth is -9.81m/s2 down
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Gravity Applets and Animations
Watch this animation and follow this hyperlink to
a cool gravity applet.GRAVITY AT WORK!!!
http//arachnoid.com/gravitation/index.html
Sir Isaac Newton explained gravity after
observing things, specifically apples, always
fall towards the Earth.
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Electromagnetic Force

• Holds atoms and molecules together
• Very strong force with a wide range
• Like charges repel and opposite charges attract
• Involves electric and magnetic properties of
  particles
  
• The electromagnetic force is carried by the
  photon
  

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Electromagnetism Formulas
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Animations for Electromagnetic Force
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The Strong Force

• Also called the nuclear force
• It is the force that holds the nucleus together.
• It has a very short range
• Holds quarks together to form hadrons
• The strong force is carried by gluon particles
  which glue quarks together.

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Strong Force
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Strong Force Animations
http//physics.bu.edu/ATLAS/guide/force-page.html

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Weak Force

• Weak Force is responsible for electrons and
  protons combining to become neutrons
  
• It is necessary for the buildup of heavy nuclei
• The weak interaction acts between both quarks and
  leptons, whereas the strong force does not act
  between leptons.
  
• The weak force is responsible for some forms of
  particle decay
  

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Weak Force
It is the weak force that causes massive leptons
and quarks to decay into lighter leptons and
quarks.
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In further notes.
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Questions!!!

• Q Which of the four fundamental forces is the
  weakest?
  
• A Gravity
• Q Which of the four fundamental forces is the
  strongest?
  
• A The Weak Force

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