From f1af1fd1de76fb566fc99c59b76cb9accf1605dd Mon Sep 17 00:00:00 2001 From: Holden Rohrer Date: Thu, 14 May 2020 16:50:46 -0400 Subject: added ap-physics1-exam --- Makefile | 4 +++- ap-physics1-exam/q1.txt | 46 ++++++++++++++++++++++++++++++++++++++++++++++ ap-physics1-exam/q2.tex | 28 ++++++++++++++++++++++++++++ 3 files changed, 77 insertions(+), 1 deletion(-) create mode 100644 ap-physics1-exam/q1.txt create mode 100644 ap-physics1-exam/q2.tex diff --git a/Makefile b/Makefile index 9f8b1fd..bce4da4 100644 --- a/Makefile +++ b/Makefile @@ -1,6 +1,6 @@ .POSIX: .SUFFIXES: .tex .pdf -PDFS = examples/mla8.pdf examples/notes.pdf examples/terms.pdf gathing-eng/module-career.pdf model-un/research-guide.pdf tech-math/comb/hw1.pdf tech-math/comb/hw3.pdf tech-math/comb/hw4.pdf tech-math/comb/hw5.pdf tech-math/comb/hw6.pdf tech-math/comb/ws1.pdf tech-math/comb/ws2.pdf tech-math/comb/ws3.pdf tech-math/comb/ws4.pdf tech-math/comb/ws5.pdf tech-math/comb/ws6.pdf tech-math/de/hw1.pdf tech-math/de/hw2.pdf tech-math/de/hw4.pdf tech-math/lect-notes.pdf tech-math/reflection.pdf wroblewski-world/dbq.pdf wroblewski-world/history-six-glasses.pdf wroblewski-world/outlines/unit1.pdf wroblewski-world/outlines/unit4.pdf wroblewski-world/outlines/unit3.pdf wroblewski-world/outlines/unit2.pdf wroblewski-world/reading-notes/compile.pdf wroblewski-world/religion-comp.pdf jones-la/heathcliff-essay.pdf jones-la/zinsser/annotations.pdf jones-la/zinsser/essay.rough.pdf jones-la/zinsser/essay.pdf jones-la/vance/annotations.pdf jones-la/vance/essay.rough.pdf jones-la/vance/essay.edit.pdf jones-la/vance/essay.pdf jones-la/quick1.pdf jones-la/letter.pdf jones-la/wiesenthal.pdf jones-la/persuas.pdf jones-la/shoot.pdf jones-la/quick6.pdf jones-la/paret.pdf jones-la/gatsby-proj.pdf jones-la/rhetorical3.pdf jones-la/reflection.pdf jones-la/rules.pdf jones-la/quick5.pdf jones-la/synth.pdf jones-la/song-tttc.pdf jones-la/tttc-true.pdf +PDFS = examples/mla8.pdf examples/notes.pdf examples/terms.pdf gathing-eng/module-career.pdf model-un/research-guide.pdf tech-math/comb/hw1.pdf tech-math/comb/hw3.pdf tech-math/comb/hw4.pdf tech-math/comb/hw5.pdf tech-math/comb/hw6.pdf tech-math/comb/ws1.pdf tech-math/comb/ws2.pdf tech-math/comb/ws3.pdf tech-math/comb/ws4.pdf tech-math/comb/ws5.pdf tech-math/comb/ws6.pdf tech-math/de/hw1.pdf tech-math/de/hw2.pdf tech-math/de/hw4.pdf tech-math/lect-notes.pdf tech-math/reflection.pdf wroblewski-world/dbq.pdf wroblewski-world/history-six-glasses.pdf wroblewski-world/outlines/unit1.pdf wroblewski-world/outlines/unit4.pdf wroblewski-world/outlines/unit3.pdf wroblewski-world/outlines/unit2.pdf wroblewski-world/reading-notes/compile.pdf wroblewski-world/religion-comp.pdf jones-la/heathcliff-essay.pdf jones-la/zinsser/annotations.pdf jones-la/zinsser/essay.rough.pdf jones-la/zinsser/essay.pdf jones-la/vance/annotations.pdf jones-la/vance/essay.rough.pdf jones-la/vance/essay.edit.pdf jones-la/vance/essay.pdf jones-la/quick1.pdf jones-la/letter.pdf jones-la/wiesenthal.pdf jones-la/persuas.pdf jones-la/shoot.pdf jones-la/quick6.pdf jones-la/paret.pdf jones-la/gatsby-proj.pdf jones-la/rhetorical3.pdf jones-la/reflection.pdf jones-la/rules.pdf jones-la/quick5.pdf jones-la/synth.pdf jones-la/song-tttc.pdf jones-la/tttc-true.pdf ap-physics1-exam/q2.pdf all: $(PDFS) .tex.pdf: pdftex --jobname $* $< @@ -65,6 +65,8 @@ jones-la/synth.pdf: jones-la/synth.tex jones-la/song-tttc.pdf: jones-la/song-tttc.tex jones-la/tttc-true.pdf: jones-la/tttc-true.tex +ap-physics1-exam/q2.pdf: ap-physics1-exam/q2.tex + clean: find . -type f | grep -e ".*\.pdf" | xargs rm diff --git a/ap-physics1-exam/q1.txt b/ap-physics1-exam/q1.txt new file mode 100644 index 0000000..b2b5c7c --- /dev/null +++ b/ap-physics1-exam/q1.txt @@ -0,0 +1,46 @@ +WY5V8181 +HR + +(a) + +Graph B is correct because the magnitude of acceleration is constant in +simple circular motion, so the magnitude of net force is proportional +and thus constant (F = ma). + +(b) + +The magnitude of tension on the string is greater than the centripetal +force on the sphere. Tension has two components, the opposite force to +gravity because the sphere is in equilibrium vertically, and the +centripetal force. The resultant of two nonzero forces is larger than +either component, so tension > centripetal force. + +(c) + +The inward acceleration needn't be as large for a very small tangential +speed to keep the sphere in constant circular motion. This means that +the centripetal force can be smaller. If the centripetal force can be +smaller but the vertical force of tension counteracting gravity is the +same, then the angle of the string and the pole is smaller. + +(d) + +This equation is consistent with part (c) because, for small values of +theta (string nearly vertical), tan(theta)*sin(theta) ~ 0, so v^2 ~ 0, +so v ~ 0 (small). + +(e) + +v^2 = gL*tan(theta)*sin(theta) +=> g = v^2 / (tan(theta) * sin(theta)). + +If v^2 were graphed on the y-axis of a graph and +(tan(theta) * sin(theta)) on the x-axis, the slope of the line of best +fit would give an experimental value of g. + +(f) + +As theta decreases, the distance of the sphere to the rod decreases. +The masses of all objects remains const, I = mr^2 for a point-like +object, and the distances from the pivot (and thus inertia) remain the +same for the rod and the platform. Therefore, as r -> 0, I -> 0. diff --git a/ap-physics1-exam/q2.tex b/ap-physics1-exam/q2.tex new file mode 100644 index 0000000..f531b2d --- /dev/null +++ b/ap-physics1-exam/q2.tex @@ -0,0 +1,28 @@ +{\obeylines% +WY5V8181 +HR +} +\noindent(a) + +Speed is absolute velocity (i.e. regardless of direction). Both A and B +have increasing absolute distance from the x-axis at every time shown on +the graph, so neither has decreasing speed. + +\noindent(b) + +At $t=0$, $t=2$, A and B are moving at the same speed because their +lines on the graph intersect. + +\noindent(c) + +Object A. + +\noindent(d) + +$$W = \Delta E.$$ +The initial velocities of both objects are zero, so their initial +energies are zero, and $$W = E_f = {1\over2}mv^2.$$ Because +$m_A = m_B,$ and $$|v_A| > |v_B| \to v_A^2 > v_B^2\hbox{ at $t=4$},$$ +object A has more energy and has thus had more net work done to it. + +\bye -- cgit