AQA A Level Physics復習筆記8.3.7 Nuclear Density
Constant Density of Nuclear Material Assuming that the nucleus is spherical, its volume is equal to: Where?R?is the nuclear radius, which is related to mass number,?A, by the equation: Where...
Alevel生物學科必讀書單！
最近，非常多同學學習Alevel生物。而生物作為一個探究人生奧秘的熱門學科，卻似乎因為專業性強，門檻高將同學們拒之于外。相信同學們都幻想過，忽然有一天學習生物變得有趣又令人著迷，再也不會枯燥了。這種想法...
AQA A Level Physics復習筆記8.3.6 Nuclear Radius Equation
Nuclear Radius Values The radius of some nuclei are shown in the table below: In general, nuclear radii are of the order 10–15?m or 1 fm The nuclear radius,?R, varies with nucleon number,?A?...
AQA A Level Physics復習筆記8.3.5 Closest Approach Estimate
Closest Approach Estimate The Coulomb equation can be used to give an estimate for the radius of a nucleus When the alpha particle reaches its closest approach (to the nucleus), all of its k...
AQA A Level Physics復習筆記8.3.4 Nuclear Radius
Estimating Nuclear Radius Closest Approach Method In the Rutherford scattering experiment, alpha particles are fired at a thin gold foil Some of the alpha particles are found to come straigh...
AQA A Level Physics復習筆記8.3.3 Nuclear Excited States
Nuclear Excited States In the same way that electrons can exist in excited states, nuclei can also exist in?excited states After an unstable nucleus emits an alpha particle, beta particle or...
AQA A Level Physics復習筆記8.3.2 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?beta-minu...
AQA A Level Physics復習筆記8.3.1 Nuclear Instability
Nuclear Stability Graph The most common elements in the universe all tend to have values of N and Z less than 20 (plus iron which has Z = 26, N = 30) Where: N = number of neutrons Z = number...
AQA A Level Physics復習筆記8.2.4 Applications of Radioactivity
Radioactive Dating The isotope carbon-14 is commonly used in radioactive dating It forms as a result of cosmic rays knocking out neutrons from nuclei, which then collide with nitrogen nuclei...
