IB DP Physics: SL復習筆記7.1.8 Half-Life
Half-Life It is impossible to know when a particular unstable nucleus will decay But the?rate?at which the activity of a sample decreases can be known This is known as the?half-life Half-life is de...
IB DP Physics: SL復習筆記7.1.7 Decay Equations
Decay Equations Changes in N and Z by Radioactive Decay There are four reasons why a nucleus might become unstable, and these determine which decay mode will occur Too many neutrons Decays through?...
IB DP Physics: SL復習筆記7.1.6 Alpha, Beta & Gamma Particles
Alpha, Beta & Gamma Particles Some elements have nuclei that are unstable This tends to be when the number of nucleons does not balance In order to become more stable, they emit particles and/o...
IB DP Physics: SL復習筆記7.1.5 Background Radiation
Background Radiation It is important to remember that radiation is a natural phenomenon Radioactive elements have?always?existed on Earth and in outer space However, human activity has added to the...
IB DP Physics: SL復習筆記7.1.4 Isotopes & Radioactive Decay
Isotopes AZX Notation A nuclide is a group of atoms containing the same number of protons and neutrons For example, 5 atoms of oxygen are all the same nuclide but are 5 separate atoms Atomic symbol...
IB DP Physics: SL復習筆記7.1.3 Emission & Absorption Spectrum
Emission & Absorption Spectrum Line Spectra Line spectra is a phenomenon that occurs when excited atoms emit light of certain wavelengths which correspond to different colours This comes from d...
IB DP Physics: SL復習筆記7.1.2 Calculating Discrete Energies
Transitions Between Energy Levels Difference in discrete energy levels The difference between two energy levels is equal to a specific photon energy The energy (hf) of the photon is given by: ΔE?=?...
IB DP Physics: SL復習筆記7.1.1 Discrete Energy Levels
Discrete Energy Levels The Photon Model Photons are fundamental particles that make up all forms of electromagnetic radiation A photon is a massless “packet” or a “quantum” of electromagnetic energ...
IB DP Physics: SL復習筆記6.2.3 Gravitational Field Strength
Gravitational Field Strength There is a universal force of attraction between all matter with?mass This force is known as the ‘force due to gravity’ or the?weight The Earth’s gravitational field is...
IB DP Physics: SL復習筆記6.2.2 Circular Orbits
Circular Orbits Since most planets and satellites have a near circular orbit, the gravitational force?FG?between the sun or another planet provides the?centripetal force?needed to stay in an orbit ...
2022年7月31日托?？荚嚳记榛仡?！
7月31日的托福考試雖然整體難度還不算高，但很明顯比之前兩次托福考試難度要高一些，不僅口語出現了全新話題，寫作也出現了新題目，讓考生分手難題提升不少。8月份是暑假最后出分的機會，考場相對少一些，考試次...
AP美國史考察內容解讀，應該如何備考？
相信很多中國學生對AP美國歷史并不是很感興趣，認為枯燥且難，學了也拿不上高分。但其實，作為一門“偏文”的AP科目，學好AP美國歷史不僅能展示出學生的學術能力，還可體現出申請者是一個敢于挑戰，全面發展的學生...
