OCR A level Physics Ultimate Revision Summary Notes

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Ultimate

Revision

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A collection of key points that will help you in your exam

,Fundamental Forces
Fundamental Force Effect Relative S treng th Rang e
S trong Nuclear experienced by nucleons 1 ~ 105m
experienced by s tatic and
Electromag netic moving charged particles 103 infinite


res pons ible for beta- decay -6
Weak Nuclear 10 110-18 m


experienced by all particles with 10-40
Gravitational infinite
mas s


⇒ In particle accelerators , protons are s mas hed tog ether
at hig h s peeds to form an array of particles s uch as :
• Baryons
• Mes ons
• Kaons
• Pions




Hadrons & Leptons
Hadrons :
↳ includes particles and antiparticles
↳ affected by s trong nuclear force
↳ examples = protons , neutrons and mes ons
↳ decay by weak nuclear force
Le ptons :
↳ includes particles and antiparticles
↳ not affected by S trong nuclear force
↳ examples = electrons , neutrinos and muons
↳ if charged they als o experience electromag netic force

, Quarks
⇒ Tog ether with leptons , quarks are the building blocks of matter
⇒ Any particle that contains quarks is called a hadron
⇒ Baryons are a combination of 3 quarks
↳ protons (uud) & neutrons (udd)
⇒ Mes ons are a combination of a quark and antiquark



Beta Decay
Be ta minus / β- → In → Ip + ♀, e + te (re-electron antineutrino)
Be ta plus / βt ⇒ Ep → In + ♀, e t ve (e-electron neutrino)


Define Chain Reaction
More neutrons are produced which g o on to produce further reactions /s plitting of
nuclei


How Are Chain Reactions Prevented In A Nuclear Reactor
• Control rods us ed
• They abs orb the neutrons