|
conversion between $\text{C}$ and $\text{K}$
|
\[
T_\mathrm{C}=T-273.15
\]
|
|
conversion between $\text{C}$ and $\text{F}$
|
\[
T_\mathrm{F}=\frac{9}{5}T_\mathrm{C}+32^\circ F
\]
|
|
proportions between $\text{K}$, $\text{C}$ and $\text{F}$.
|
\[
\Delta T_\mathrm{C}=\Delta T=\frac{5}{9}\Delta T_\mathrm{F}
\]
|
|
average coefficient of linear expansion,
depends on material.
|
\[
\alpha=\frac{\Delta L/L_i}{\Delta T}
\]
|
|
alphas for some common materials
|
Table 19.2
|
587 |
for sufficiently small changes in $\Delta T$
or for sufficiently small $\frac{\Delta L}{L_i},$
$\alpha$ is constant.
|
|
|
$\alpha=$ average
coefficient of linear expansion.
Holds for small changes
|
\[
L_f-L_i=\alpha L_i\left(T_f-T_i\right)
\]
|
|
$2\alpha=$ average
coefficient of area expansion
|
\[
A_f-A_i=2\alpha A_i\left(T_f-T_i\right)
\]
|
|
$3\alpha=$ average
coefficient of volume expansion
|
\[
V_f-V_i=3\alpha V_i\left(T_f-T_i\right)
\]
|
|
Ideal gas law.
$P=$ Pressure,
$V=$ Volume,
$n=$ number of moles molecules,
$T=$ temperature,
$R=$ universal gas constant.
The gas must be trapped, which is
to say that $n$ is constant.
|
\[
PV=nRT
\]
|
|
universal gas constant.
|
\[
R=8.315\frac{\mathrm{J}}{\mathrm{mol\cdot K}}
\]
|
|
Ideal gas law expressed in terms of number
of molecules
instead of number of moles.
($k_B$
is Boltzmann's Constant.)
|
\[
PV=Nk_BT
\]
|
|
Boltzmann’s Constant.
|
\[
k_B=\frac{R}{N_A}=1.38\times{10}^{-23}\frac{\mathrm{J} }{\mathrm{K}}
\]
|
|
Boyle’s Law.
This law is captured by the Ideal Gas Law.
|
\[
P\propto V^{-1}
\]
|
|
Law of Charles Gay-Lussac.
This law is captured by the
Ideal Gas Law.
|
\[
V\propto T
\]
|
|
pressure
|
\[
\left[P\right]=\frac{\left[F\right]}{\left[L^2\right]}=\frac{\left[F\right]}{\left[A\right]}
\]
|
|
pressure $\times$ volume = energy
|
\[
\left[PV\right]=\left[E\right]
\]
|
|
SI units for pressure $\times$ volume
|
\[
\left[PV\right]_{\mathrm{SI}}=\mathrm{J}=N\cdot m
\]
|
|
pascal, pressure units
|
\[
1\ \mathrm{Pa}=1=\frac{\mathrm{N}}{\mathrm{m}^2}
\]
|