1. Particle Interactions
Concept of exchange particles to explain forces between elementary particles
The electromagnetic force; virtual photons as the exchange particle.
The weak interaction limited β-, β+ decay, electron capture and electron-proton
collisions; W+ and W- as the exchange particles.
Simple Feynman diagrams to represent the above reactions or interactions in
terms of particles going in and out and exchange particles.

2. 1
Concept of exchange particles to explain forces between elementary particles.

3. 2 Force Exchange Particle electromagnetic Photon (γ) weak interaction
W+, W-
Strong interaction
Gluon (g)

4. 3 The electromagnetic Interaction
Possible areas of questioning
Repulsion/Attraction of charged particles
Annihilation
Pair Creation

5. Simple Repulsion between like charged electrons
Simple Repulsion between like charged electrons. The particle of exchange is the photon e- γ

6. Electromagnetic Interaction Annihilation and Pair Creation
THESE PROCESSES ARE EXACT OPPOSITES OF ONE ANOTHER

7. Weak Interaction
The weak interaction limited to β-, β+ decay, electron capture and electron-proton collisions;
W+ and W- as the exchange particles.

8. β- decay Decay at the Quark Level
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9. β+ decay Decay at the Quark LevelW+ u
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10. Electron Capture And Electron Proton Collisions At The Quark LevelW-
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