What did early physicists believe about atoms?,
Atoms were thought to be indivisible solid spheres like billiard balls.
What evidence suggested that protons and neutrons are not fundamental particles?
High-energy collisions revealed that protons and neutrons are made of smaller particles called quarks.
Who proposed the existence of quarks and when?
,Murray Gell-Mann in 1964.
How many flavours (types) of quarks are there?
**Six: **up, down, strange, charm, bottom, top.
What is the quark composition of a proton?
Two up quarks and one down quark (uud).
What is the quark composition of a neutron?
,One up quark and two down quarks (udd).
What name is given to particles made of quarks?,
Hadrons.
What are baryons?,
Hadrons made of three quarks (e.g., protons and neutrons).
What are mesons?
Hadrons made of one quark and one antiquark.
What are leptons?,
Elementary particles not made of quarks, e.g., electron, muon, tau, and their neutrinos.
Give an example of a lepton that is part of the atom.,
The electron.
What is the difference between quarks and leptons?,
Quarks experience the strong nuclear force; leptons do not.
Why are particle accelerators important in discovering subatomic particles?,
They smash particles at high energies to reveal new fundamental particles.
What model of matter incorporates quarks, leptons, and fundamental forces?
,The Standard Model of Particle Physics.
What is a synchrotron?
A particle accelerator that uses magnetic fields to bend electrons moving at near light speed, producing synchrotron radiation (infrared, UV, visible, and X-rays).
Who predicted the existence of the neutrino and why?
Wolfgang Pauli in 1930, to explain missing energy, momentum, and spin in beta decay.
What are the properties of neutrinos?
Nearly massless (~10⁻³⁶ kg), neutral, rarely interact with matter, pass through Earth almost unaffected.
Who predicted the Higgs boson and when was it discovered?
Peter Higgs (1964). It was confirmed in 2012 at CERN’s Large Hadron Collider.
What role does the Higgs boson play in physics?
It is associated with the Higgs field, which gives mass to fundamental particles.
What is the Large Hadron Collider (LHC)?
The largest particle accelerator (27 km circumference) at CERN, used to collide protons/ions at energies up to 13 TeV.
What are some goals of the LHC?
Investigate Higgs boson, search for dark matter/energy, explore quark–gluon plasma, study matter vs antimatter imbalance.
What is a cyclotron and who built the first one?
A circular particle accelerator that repeatedly accelerates particles with alternating voltage. Built by Ernest Lawrence in 1932.
How does a cyclotron work?
Particles spiral outward between two ‘dees’ under a magnetic field, gaining energy each pass until exiting to hit a target.
What particle did Hideki Yukawa predict in 1935?
The meson, proposed to explain the strong nuclear force holding nucleons together. Confirmed in 1947.
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Units14
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Formula sheet Knowledge121
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Formula sheet Knowledge 225
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Formulas worth remembering9
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Chapter 5 charged particles19
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Chapter 7 Electromagnetic induction18
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Chapter 9 Electromagnetic spectrum17
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Chapter 9b Spectroscopy21
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Chapter 10 light wave model20
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Chapter 10b Polorisation11
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Chapter 11 - Quantum model of light15
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Chapter 12 - special_relativity20
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Chapter 13 - Origin of elements23
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Chapter 14 Structure of the atom15
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Chapter 15 - Quantum mechanical nature of the atom20
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Chapter 15 De Broglie11
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Chapter 16 Radioactive decay20
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Chapter 16 -half life13
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Chapter 16 Fission and fusion14
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Chapter 16- Energy from nuclear reactions18
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Chapter 17 Deep inside the atom29
