[LON-CAPA-cvs] cvs: modules /gerd/discussions/paper discussions.tex
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Mon, 18 Apr 2005 21:12:49 -0000
www Mon Apr 18 17:12:49 2005 EDT
Modified files:
/modules/gerd/discussions/paper discussions.tex
Log:
Example of discussion contributions.
Index: modules/gerd/discussions/paper/discussions.tex
diff -u modules/gerd/discussions/paper/discussions.tex:1.12 modules/gerd/discussions/paper/discussions.tex:1.13
--- modules/gerd/discussions/paper/discussions.tex:1.12 Sat Apr 16 11:40:11 2005
+++ modules/gerd/discussions/paper/discussions.tex Mon Apr 18 17:12:49 2005
@@ -176,7 +176,12 @@
Why is it that homeworks are getting longer and longer?
&
Everyone keeps saying they figured it out, but no one is telling how. Please let us know because we have tried everything!
-&&\\\hline
+&
+Bless your heart, and thank you for having the patience to explain this vector addition stuff to people like me who're really struggling with this vector and sin, cos stuff. It's
+starting to all come together.
+&
+Sometimes, when I think of the word ``physics,'' I get a sickening feeling in the pit of my stomach. It's sort of like a burning sensation.
+\\\hline
Surface&
If this is extra credit, does that mean it won't be on the exam?
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@@ -190,22 +195,16 @@
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Use this formula: T(final) = (m1c1T1+m2c2T2) / (m1c1+m2c2). Convert temp to Kelvin and then for your final answer convert back to Cel.&
Thanks, I just realized it. I was supposed to solve for cos(c) by moving everything to the other side of the equation then take the cos$\hat{ }$-1 of that.&
-Conservation of Energy Problem\newline
-KE(initial)+Heat Energy(initial)=Latent Heat\newline
-so ... .5mv$\hat{ }$2(bullet)+m*(c-lead)*(change in T)=m(of the water)*L\newline
-m(of the water) is what you want to find\newline
-L is L h2o fusion - given\newline
-m - mass of bullet - given\newline
-v- given\newline
-You have to convert the c(lead) and the L h20 fusion, you do this by multiplying them by (4.186)(1000)\newline
-The final answer units are Kg.\newline
-I don't know if that makes sense .. but I hope so.\\\hline
+Use equation for torque:\newline
+torque = current * area * sin(90)\newline
+It is 90 because it is a rectangle.\newline
+Once you solve for torque multiply it by the N they give you and that is your answer. Make sure to convert your mA to A and cm to m before putting into equation.
+\\\hline
Conceptual&
&
I thought you could use the equations for rolling without slipping ... can anyone clarify as to why not?
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-Why can't you call Vf negative, and say Vi is moving in the positive direction? Depending on what you call positive and negative, you get two different answers for Vf (two different numbers, not just
-a different sign).
+Do not add 90 degrees. Your answer depends on which quadrant your angle is in. You want the answer to be in the upper right quadrant, so add 180 to the absolute value of your answer if you have a negative x component value to find the angle you are looking for.
&
I have the correct answer, but I don't understand why it is correct. Why would there be an acceleration at the ball's highest point? Why wouldn't it be zero?
\end{tabular}