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Key Equations

PhysicsKey Equations

Key Equations

22.1 The Structure of the Atom

energy of hydrogen electron in an orbital

E_{n} = - \frac{13.6 eV}{n^{2}} (n = 1, 2, 3, ...)

energy of any hydrogen-like electron in orbital

E_{n} = \frac{Z^{2}}{n^{2}} E_{o} (n = 1, 2, 3, ...)

wavelength of light emitted by an electron changing states

\frac{1}{λ} = R (\frac{1}{n_{f}^{2}} - \frac{1}{n_{i}^{2}})

wavelength of an orbital

n λ_{n} = 2 π r_{n} (n = 1, 2, 3, ...)

heisenberg’s uncertainty principle

Δ x Δ p \geq \frac{h}{4 π}

22.2 Nuclear Forces and Radioactivity

alpha decay equation

{}_{Z}^{A}X_{N} \to {}_{Z - 2}^{A - 4}Y_{N} + {}_{2}^{4}H e_{}

beta decay equation

{}_{Z}^{A}X_{N} \to {}_{Z + 1}^{A}Y_{N - 1} + e + v

gamma decay equation

{}_{Z}^{A}X_{N} \to X_{N} + γ

22.3 Half Life and Radiometric Dating

radioactive half-life

N = N_{O} e^{- λ t}

22.4 Nuclear Fission and Fusion

energy–mass conversion

E = m c^{2}

proton-proton chain

2 e− + 4^{1} H \to 4 He + 2 v_{e} + 6 γ

22.5 Medical Applications of Radioactivity: Diagnostic Imaging and Radiation

roentgen equivalent man

rem = rad \times RBE

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- Book title: Physics
- Publication date: Mar 26, 2020
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