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diff --git a/Master/texmf-dist/doc/latex/examdesign/exampleb.tex b/Master/texmf-dist/doc/latex/examdesign/exampleb.tex new file mode 100644 index 00000000000..d5a73bd9098 --- /dev/null +++ b/Master/texmf-dist/doc/latex/examdesign/exampleb.tex @@ -0,0 +1,113 @@ +\documentclass[10pt, onekey]{exam} +\Fullpages +\NumberOfVersions{4} +\def\eV{\mbox{eV}} + +\begin{document} + +\begin{frontmatter} +\vspace*{3in} +\begin{center} + \huge Modern Physics \\[6pt] + \Large Final Exam +\end{center} +\vfill +\begin{flushright} + Name: \rule{3in}{.4pt} \\[10pt] + Student I.D.: \rule{3in}{.4pt} +\end{flushright} +\end{frontmatter} + +\begin{examtop} +\end{examtop} + +\begin{shortanswer}[title={\Large Short Answer (10 pts each)},suppressprefix] +Answer all problems in as thorough detail as possible. Be sure to include all +your work. Partial credit will be given even if the answer is not fully correct. + +\begin{question} + Determine the charge in the rest mass of a system consisting of a proton + and an electron as the two particles combine to form a hydrogen atom. The + ionization energy of hydrogen is 13.6 eV. + \examvspace*{1.5in} + \begin{answer} + The rest mass of the proton is $1.672649 \times 10^{-27}$kg; that of the + electron is $9.109534 \times 10^{-31}$kg. When the electron and proton + combine to form a hydrogen atom, the ionization energy of 13.6 eV is + released as ultraviolet radiation. The rest mass of the hydrogen atom is + therefore smaller than the sum of the electron and proton rest masses by + the amount + \[ + \Delta M = {(13.6 \eV)(1.6 \times 10^{-19} J/\eV) \over (3 \times 10^8 m/s)^2} + = 2.42 \times 10^{-35}kg + \] + \end{answer} +\end{question} + +\begin{question} + The Eiffel Tower in Paris is 300m tall. What is the fractional gravitational + red shift due to this elevation difference? + \examvspace*{1in} + \begin{answer} + \[ + {\delta\nu \over \nu} = {gH \over c^2} = {(9.8m/s^2)(300m) \over + (3 \times 10^8 m/s)^2} = 3.27\times 10^{-14} + \] + \end{answer} +\end{question} + +\begin{question} + Derive Stefan's law from Planck's law. Using that result, obtain an + expression for the Stefan-Boltzmann constant $\sigma$ in terms of known + physical constants and determine its value. + \examvspace*{1.5in} + \begin{answer} + The radiance + \end{answer} +\end{question} + +\begin{question} + Calculate the density of an object of one solar mass whose radius is the + critical Schwarzschild radius. Compare this density with the nuclear + density of approximately $2.3 \times 10^{17} kg/m^3$. + \examvspace*{1.5in} + \begin{answer} + The mass of the sun is $2 \times 10^{30} kg$. The universal gravitational + constant is $6.67 \times 10^{-11} N\cdot m^2/kg^2$. + + The Schwarzschild radius of one solar mass is + \begin{eqnarray*} + R_c & = & {2(2 \times 10^{30}lg)(6.67 \times 10^{-11} N\cdot m62/kg^2) + \over (3 \times 10^8 m/s)^2} \\ + & = & 2.96 \times 10^3 m \approx 3 km + \end{eqnarray*} + If the sun collapsed to a sphere of 3 km radius without loss of mass, it + would then be a black hole. The mass density would be + \[ + \rho = {M \over V} = {2 \times 10^{30} kg \over ({4\pi \over 3}) + (2.96 \times 10^3 m)^3} = 1.84 \times 10^{19} kg/m^3 + \] + \end{answer} +\end{question} +\end{shortanswer} + +\begin{endmatter} + \vspace*{1.5in} + \centerline{\Large A Partial List of Fundamental Constants} + \bigskip + \begin{center} + \begin{tabular}{lcl} + Constant & Symbol & Approximate Value \\ \hline + Speed of light in vacuum & $c$ & $3.00 \times 10^8$m/s \\ + Permeability of vacuum & $\mu_0$ & $12.6 \times 10^{-7}$H/m \\ + Permittivity of vacuum & $\epsilon_0$ & $8.85 \times 10^{-12}$F/m \\ + Magnetic flux quantum & $\phi_0 = {h \over 2e}$ & $2.07 \times 10^{-15}$Wb \\ + Electron mass & $m_e$ & $9.11 \times 10^{-31}$kg \\ + Proton mass & $m_p$ & $1.673 \times 10^{-27}$kg \\ + Neutron mass & $m_n$ & $1.675 \times 10^{-27}$kg \\ + Proton-electron mass ratio & $m_p \over m_e$ & 1836 + \end{tabular} + \end{center} +\end{endmatter} + +\end{document} |