$ \newcommand{\e}[1]{ \times 10^{#1}} $
constants
$m_e = 9.11\e{-31} kg = .511 \frac{MeV}{c^2} = 5.4858\e{-4} u$
$m_p = 1.673\e{-27} kg = 938 \frac{MeV}{c^2} = 1.007276 u$
$m_n = 1.675\e{-27} kg = 940 \frac{MeV}{c^2} = 1.008665 u$
$u = 1.6605\e{-27} kg = 931.5 \frac{MeV}{c^2}$
$e = 1.6012\e{-19} C$
$\mu_0 = 4\pi\e{-7}$
$k = 8.988\e9 \frac{Nm^2}{C^2}$
$\varepsilon_0 = 8.854\e{-12} \frac{F}{m}$
$c = 2.998\e8 \frac{m}{s}$
$h = 6.626\e{-34} Js = 4.136\e{-15} eVs$
$T = 1.6\e{-19}$
$E_1 = -13.6 eV$
$r_0 = 1.2\e{-15} m$
equations
$\varepsilon_0 = \frac1{4\pi k} = \frac1{\mu_0c^2}$
electric fields
$E = \frac{\sigma}{\varepsilon_0}$
$\Phi_E = \vec E \cdot \vec A = EA\cos \theta = \frac{q_A}{\varepsilon_0}$
$\vec F_E = \frac{kqQ}{r^2} = Q \vec E$
$W = \vec F \Delta x \cos \theta$
$\Delta U = -\Delta E_k = -W$
$\Delta V = \frac{\Delta U}{q_0} = -\vec E \Delta x$
$V = \frac{kQ}r$
capacitance
$V = Ed$
$Q = \sigma A$
$C = \frac{Q}V = kC_0$
$U = \frac{CV^2}2$
electric currents
$V = IR$
$P = IV$
$I = \frac{\Delta Q}{\Delta t}$
$I = v_DAnq$
$I_{rms} = \frac{I_0}{\sqrt2}$
$R = \frac{\rho \ell}A$
dc circuits
$\tau = RC$
$V_0 = \frac{Q_0}C$
$I_0 = \frac{V_0}R$
$Q_{max} = CV_B$
$\sum I_{in} = \sum I_{out}$
$\sum V_{loop} = 0$
series
$\sum Q = Q_1 = Q_2 = \cdots = Q_n$
$\frac1{\sum C} = \frac1{C_1} + \frac1{C_2} + \cdots + \frac1{C_n}$
$\sum U = \frac{Q_1^2}{2C_1} + \frac{Q_2^2}{2C_2} + \cdots + \frac{Q_n^2}{2C_n}$
$\sum R = R_1 + R_2 + \cdots + R_n$
parallel
$\sum V = V_1 = V_2 = \cdots + R_n$
$\sum C = C_1 + C_2 + \cdots + C_n$
$\sum U = \frac{Q_1}{2C_1} + \frac{Q_2}{2C_2} + \cdots + \frac{Q_n}{2C_n}$
$\frac1{\sum R} = \frac1{R_1} + \frac1{R_2} + \cdots + \frac1{R_n}$
rc circuits
$i = I_0 e^{\frac{-t}\tau}$
$V_R = I_0 R e^{\frac{-t}\tau}$
$U = \frac{q^2}{2C}$
$P = i^2 R$
charging
$q = Q_{max} \left(1 - e^{\frac{-t}\tau}\right)$
$V_C = V_B \left(1 - e^{\frac{-t}\tau}\right)$
discharging
$q = Q_{max} e^{\frac{-t}\tau}$
$V_C = V_B e^{\frac{-t}\tau}$
magnetism
$\vec F_B = q \vec v \cdot \vec B = qvB\sin\theta$
$F_B = \frac{mv^2}{R} = qvB$
$\frac{F_M}{\ell} = BI\sin\theta$
$B = \frac{\mu_0 I}{2 \pi r} = \frac{\mu_0 I N}{\ell}$
$\frac{F_{21}}{\Delta \ell} = \frac{\mu_0 I_1 I_2}{2 \pi d}$
electromagnetic induction
$\mathcal{E} = \left|\frac{\Delta \Phi_B}{\Delta t}\right| = -vBL = NBAq$
$I_{avg} = \frac{\left|\mathcal{E}\right|}R$
$\Delta \Phi_B = B \Delta A = \Delta B A$
$U = \frac{LI^2}2 = \frac{B^2V_{ol}}{2\mu_0}= \frac{B^2\pi r^2\ell}{2\mu_0}$
$\tau = \vec \mu \cdot \vec B$
$P = \vec F \cdot \vec v = \frac{\left(B \ell v\right)^2}R$
$\frac{N_P}{N_S} = \frac{V_P}{V_S} = \frac{I_S}{V_P}$
electromagnetic waves
$v = f\lambda$
$\vec{S} = \frac{EB}{2\mu_0} = \frac{P}A$
$E = \frac{I}{A\mathcal{E}_0} = cB$
$\sum U = U_E + U_B = \mathcal{E}_0E^2$
$U_E = \frac{\mathcal{E}_oE^2}2$
$U_B = \frac{B^2}{2\mu_0}$
$S = \frac{CB^2}{\mu_0} = \frac{\Delta U}{A\Delta t}$
optics
$\frac1{d_0} + \frac1{d_i} = \frac1{f} = \frac2{r}$
$\frac1{f} = (n-1)\left(\frac1{R_1}-\frac1{R_2}\right)$
$M = \frac{-d_i}{d_0} = \frac{h_i}{h_0}$
$n_1\sin\theta_1 = n_2\sin\theta_2$
$\lambda_m = \frac{\lambda_v}n$
special theory of relativity
$\Delta t = \gamma \Delta t_0$
$L = \frac{L_0}{\gamma}$
$\gamma = \frac1{\sqrt{1-\frac{v^2}{c^2}}}$
$v = c \sqrt{1-\frac1{\gamma^2}}$
quantum mechanics
$\hbar = \frac{h}{2\pi}$
$\Delta x \Delta p \gtrsim \hbar$
$\Delta E \Delta t \gtrsim \hbar$
$E_n = \frac{Z^2}{n^2}(-13.6eV)$
nuclear physics
$r = r_0 A^{1/3}$
$N = N_0e^{-\lambda t}$
$A = \lambda N$
info
prefixes
name | prefix | power |
---|---|---|
exa | E | $10^{18}$ |
peta | P | $10^{15}$ |
tera | T | $10^{12}$ |
giga | G | $10^9$ |
mega | M | $10^6$ |
kilo | k | $10^3$ |
hecto | h | $10^2$ |
deca | da | $10^1$ |
- | - | - |
deci | d | $10^{-1}$ |
centi | c | $10^{-2}$ |
milli | m | $10^{-3}$ |
mirco | μ | $10^{-6}$ |
nano | n | $10^{-9}$ |
pico | p | $10^{-12}$ |
femto | f | $10^{-15}$ |
atto | a | $10^{-18}$ |
right hand rules
hand | vector |
---|---|
fingers | $\vec v$ or $I$ |
palm | $\vec B$ |
thumb | $\vec F$ |
quantum numbers
(n, ℓ, m, s) |
---|
n = 1, 2, 3 … ∞ |
ℓ = 0 … n-1 |
m = -ℓ … +ℓ |
s = ±½ |