Fichas
Physics Unit One Equations and Formulae
Fichas del conjunto (29)
- 1What do each of these stand for in the isotope notation?63 = number of protons and neutrons
29 = number of protons
Cu = the chemical symbol - 2What is a nucleon?A nucleon is a proton or neutron in the nucleus
- 3How do you work out specific charge?specific charge = charge/mass
- 4What is an isotope?An isotope of an atom is one with the same number of protons but different numbers of neutrons
- 5What is the Strong Nuclear Force and list two facts about it.The strong nuclear force overcomes the electrostatic force of repulsion between protons in the nucleus and keeps them and neutrons together.
Its range is no more than 3-4 fm, it has the same effect on 2 protons as 2 neutrons or a proton and neutron. - 6Describe alpha decayAlpha decay is where the nucleus emits an alpha particle and forms a new nucleus
- 7Describe beta decayBeta decay is where a neutron in the nucleus changes into a proton, a beta particle is created in the nucleus and is instantly emitted
- 8how do you work out wavelength?Note: c = 3.00x108 in the formulae booklet
- 9What does E = hf calculate?photon energy
- 10How do you work out the power of a laser beam?nhf
(n= number of photons per second; h=Planck constant; f=frequency of photons) - 11Draw a diagram of particle annihilation
- 12Draw a diagram of pair production
- 13For annihilation, how do you work out the minimum energy of each photon produced?hf(min) = E(0)
- 14In pair production, how do you work out minimum energy of each photon needed?hf(min) = 2E(0)
- 15Draw two Feynman diagrams for NEUTRINO-BARYON INTERACTION (neutron-neutrino, proton-anti neutrino)
- 16Draw the beta+ and beta- Feynman diagrams
- 17Draw the electron capture Feynman diagram
- 18What are hadrons?particles and antiparticles that can interact through strong interaction and electromagnetic interaction if charged. Apart from protons, they all decay through weak interaction.
EG. protons, neutrons, pi mesons, K mesons - 19What are leptons?Particles and antiparticles that do not interact through strong interaction because they are fundamental particles; interact through weak interaction and EM in charged. Leptons do not have any quarks.
EG. electrons, muons, neutrinos - 20How are hadrons further sub-divided?Baryons: decay into protons (direct or indirect), they consist of 3 quarks
Mesons: do not include protons in their decay products (K mesons and pi mesons), they consist of a quark and an antiquark - 21What is the only similarity between hardons and leptons?they have the same rest masses
- 22What is the quark combination of a proton?uud
- 23What is udd the quark combination for?neutron
- 24How does conservation of baryon number work?+1 to any baryon
-1 to any antibaryon
0 to any meson or lepton - 25how do you work out the energy of a photon?=hf
- 26f=ϕ/h calculates what?threshold frequency
- 27What is the definition of excitation?Where an incident electron collides with an electron in a particular shell. Energy is transferred which allows the electron to transition to a higher state if the collision is of exact energy.
- 28What is the definition of de-excitation?This is where an electron falls to a lower energy level, emitting a photon of energy equal to the difference in energy levels. As these transitions are between definite levels, the energy of each photon can only take certain values.
- 29How does fluorescence work?Fluorescent tubes use the photon emission principle to produce light.
The tubes are filled with mercury atoms which become excited due to collisions with fast moving free electrons accelerated by the high voltage.
These atoms de-excite, emitting mostly UV radiation. The inside of the tubing is coated with phosphorus which absorbs UV photons, before de-exciting, emitting useful visible light.
Información
- Descripción
- All equations and formulae. http://revise.im/physics/unit-1/matter-and-radiation (really useful website)
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- natashaaaa
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