1. ### Direction of friction: deceleration and turning

Thank you for your taking the time to write a reply, Doc Al! :) I should warn you: I'm not good at understanding physics, but if I don't understand it, then unless a problem looks identical to the one before, I'm at a bit of a loss, so here's hoping that I can develop this "physical intuition."...
2. ### Direction of friction: deceleration and turning

Hi! :) I'm confused about the direction of the friction vector when we decelerate and when we turn. I've memorized the directions (if I decelerate going east, friction is aimed west; if I am in a flat circle and going around it, friction points to the middle), but they don't exactly make sense...
3. ### Enthalpy equations with pressure/volume assumptions

I'm trying to learn the various equations of enthalpy with certain assumptions, but I couldn't understand where they came from. So, I tried to derive them myself, but now I'm lost beyond reason. I'm getting confused between the various forms of the enthalpy equation, depending on constant...
4. ### Heat engines: how can we yield work?

Thank you all for your replies: I'm getting closer in understanding! Right! :D The area under the PV curve is equal to the work done: I do get that. What I didn't get was why the second curve (for the compression) is a different curve than the original one. Thank you, Andrew Mason: I now...
5. ### Heat engines: how can we yield work?

So, I'm studying for the MCAT. There..I've said it. :) But, it's not a homework question: I just don't understand the concept. My study book's thermodynamics section includes a very rough sketch of a heat engine to describe the 2nd Law of Thermodynamics. A side note in the text says that if...
6. ### Find capacitance from time, power, and voltage

Ohhhhh, OK, right, right, right. We just went over those exponential curves today. That makes sense: it wasn't 16.67 amps at the very beginning. Whew...all right; thank you! ~Ibrahim~
7. ### Find capacitance from time, power, and voltage

Energy delivered to that stored on the capacitor....the U = .5QV formula! No: I just tried it and it worked!!!!!!!!!!!!!! This time, instead, I got .06 coulombs as the charge, twice the charge compared to my previous attempt. I completely forgot about that one. But, out of curiosity, why did...
8. ### Find capacitance from time, power, and voltage

1. Homework Statement A flashlight uses 6.0J in 1.8ms (0.0018 seconds). First question: find the power. Got it: 3333W (3.3E3 with two sig figs, which is the accepted answer in the online system). The real problem: find the capacitance if the flashlight uses 200V. 2. Homework Equations...
9. ### Work = -delta U

Oh, crap. Friction is a non-conservative force: it depends on the path. There are no conservative forces acting, only non-conservative (friction). 0J = 0J. Got it. Thanks for the solution, however simple! ~Ibrahim~
10. ### Work = -delta U

1. Homework Statement Work done by conservative forces = -\DeltaU 2. Homework Equations Above. 3. The Attempt at a Solution Here is the whole equation: Wc+ Wnc = \DeltaK. Wnc = \DeltaK + \DeltaU. So, Wc = -\DeltaU. But, for example, how does that apply in a...
11. ### Boron Neutron Capture Therapy (B10->B11)

Hmm...well, I actually don't speak Turkish. :( From what Google Translate tells me, yeah, you're right. There aren't too many resources online which is the reason why I created this thread. I would try looking through this thread. Is this for a homework assignment? What information do you...
12. ### Boron Neutron Capture Therapy (B10->B11)

Do you have any specific questions? Have you looked at the Wikipedia page for it? MIT has an oldish page on it, too. ~Ibrahim~
13. ### Equilibrium Titration?

Whoops, you're definitely right. :redface: It's a .05M solution that they took 25ml, not a .1M solution. Good call. I guess you titrated it a bit too much because, even though they're close, I'm guessing that it has a K>1 so the equilibrium concentration would have been even lower...
14. ### Term Paper: Is the brain immunologically privileged?

Re: Term Paper: "Is the brain immunologically privileged?" :) Ooh, yeah. :D Those sound good! I did a project on boron neutron capture therapy a while back (it was legit made awesome by none other than folks here at PF!) and it was a way to bypass the blood brain barrier. Definitely very...
15. ### Equilibrium Titration?

Oh, no, it's definitely OK. Another set of eyes always helps. :) I think it took 25ml of a solution of a .1M Ag+/.1M Fe2+. So, .100 mols/1000ml x 25ml = .0025mols of Ag+ initially, .0013mols @ equilibrium. ~Ibrahim~