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1. ## Physics question...

A 2 kg mass (m1) and a 3 kg mass (m2) are attached to a lightweight cord that passes over a frictionless pulley. Assume the positive direction of motion to be when the smaller object moves upward and the larger mass moves downward. Okay...I went around trying to solve this as a normal tension problem...going like this: T - (m1)g = (m1)a and T - (m2)g = (m1)a (g = 9.8, a = acceleration) therefore: T = (m1)a + (m1)g and T = (m2)a + (m2)g (m2)a + (m20g = (m1)a + (m2)g solving that gives: a = 9.8 (meters per second squared) the answer key says: 1.96 (meters per second squared) My answer makes more sense to me...but I have a feeling I'm wrong (I get the feeling physics likes to chuck intuition out the window). Is the answer key correct?
2. ## Hacking Challenges

http://www.hackthissite.org - has a whole bunch of challenges from Beginner to Uber hacker. http://www.mod-x.co.uk/main.php - Neat wargame. I'm on the second level on this one. I like this one the best so far. http://3564020356.org/ - Haven't gotten around to doing this one yet, but you need to solve riddles and puzzles and you need to solve one in the beginning to register. http://www.hackquest.de/ - this one has an interesting beginning challenge. Haven't solved it yet. http://www.hackits.de - this one looks good too. http://www.slyfx.com/ - similar to the rest. http://aspect.bestweb.net/ - similar to the rest. http://www.bright-shadows.net/ - Wow! This site has a heck of a lot of challenges. They number in the 100s! Try it out. Eh...too bad dievo.org is down.
3. ## Hacking Challenges

OH SHIT!!! You're right! Dievo as we knew it is no more!!! Apparently, they aren't able to keep up with the costs anymore or something, and they are giving some of their challenges away to other websites, and the remaining challenges are being dismantled. Time to find a new hacking site. I'll post what I find here.
4. ## Hacking Challenges

Uhh...no...the Hook is still there. See the little menu thing up there? Choose Wargames in that. Then choose Hook, Neophyte, etc. No new owner, just a new look.
5. ## People of the Jewish faith you have known.

Hmm, I know a lot of Jews too, most of them are about my age (16-17) and are very nice people. Why is this thread "demeaning"....again, he just wants to know all the Jewish people you know, and how they were like. What's wrong with that? Maybe he'd like to see if Jews really fit in with the general belief of being super rich war mongering mega geniuses who want to rule the world and cheat god. That's what most people who don't know (but strongly believe they do know jews) Jews describe them as.
6. ## Middle Eastern associates.

Wow, mooey. You've got me confused. I couldn't figure out a thing by reading your posts. Can you perhaps tell me in point form what the entire point of all those long sentences and posts were? By the way, I do see a point to this thread. It helps us compare our own experiences with the ones we most often hear (the bad ones) through the media. It helps us to really see reality. I think what Rebiu really meant here was not "Middle Eastern" but "Muslim". This confusion between the terms is in fact quite understandable, as it is what we see on the media in general: terrorists = muslims = middle easterners. Oh, another thing, I live in an area quite close to a Jewish neigbourhood, so I know a lot of Jews and I am glad to say am friends with many of them. However, I do notice that about half of them who have visited Israel will tell me about some person or family they knew was affected by a terrorist attack...it's made me wonder if they are telling the truth or just grabbing for some attention. Are they telling the truth? If so, heck, there's a lot of innocent Israelis dying every year, and I totally understand the situation Israel is in. Do any of you know any official numbers about the number of innocent Israelis killed every year?
7. ## Hacking Challenges

Yeah, the site's open again. They had some major upgrades to it. There are some new challenges too. http://www.dievo.org Be advised that you will need Firefox, Netscape, or some other browser. IE does not work.
8. ## Blocking Internet Access at certain times

No one knows of any?
9. ## Blocking Internet Access at certain times

Are there any freeware programs that can completely block my computer from accessing the internet in any way or form at certain times specified by me? Also, I have a DI-604 Dlink router, is there any way I can configure it to block any internet access at certain times? If there are no good freeware programs that can do it, are there any commercial products that can accomplish the task? Thanks for your help.
10. ## How does moss help the forest around it?

I see...which are these organisms that depend upon moss?
11. ## How does moss help the forest around it?

I'd like to know how moss helps the forest around it. What does it do that is beneficial to the forest, or which organisms depend upon moss for survival? Lets say we had a forest, and a lot of the moss in it died. How would the forest be affected?
12. ## Kuru prion questions

I am doing research on the Kuru disease now, which I learn is caused by a prion, and infectious protein. Now what I'd like to know is that what exactly does the prion do that causes the different brain problems? One thing I read on Wikipedia under the Prion article is that the PrP^Sc protein which is somewhat similar to the HuPrP^Sc (kuru prion protein) contains a lot more of a amino acid structure called "beta sheet". This beta sheet causes amyloid aggregation. Now what exactly is amyloid aggregation? The article for amyloids in Wikipedia didn't tell me much apart from the fact that it's plays a role in certain brain diseases, and that it's thin, fibrous and made up of proteins. That's how I understood the first sentence (which is really the important sentence). Would I be correct? So the HuPrP^Sc protein forms these long fibrils because of these beta sheets, and that causes many problems in the brain. I understood this bit from this site: http://www.ibridgenetwork.org/technology.asp?sID=01E525E2E6BC4B6EA4F69D25DBE7AF5F&page=1361. This is the paragraph that is important: "Conformational diseases," share a common etiology whereby proteins fold irregularly to produce structural flaws. These flaws result in the proteins unnaturally aggregating and thereafter precipitating as fibrils from their solvents. Such solvents include blood, urine, water, lymph, cerebrospinal fluid, and other physiological fluids. Diseases such as sickle cell anemia, amyloid light chain disease, senile systemic amyloidosis, Alzheimer's, and prion encephalopathies including kuru and "mad cow" disease or BSE, are the result of protein conformation anomalies. So why are these fibrils dangerous? What problems do they cause? I can't seem to find that information on Google, because it's buried under loads of scientific jargon that complicates it a lot, and leads to me to research a lot of other different things. I tried doing spending quite a bit of time on it (some 4-5 hours) but I didn't come up with anything worthwhile on the issue. I did a search on Wikipedia (thank god for wikipedia) and got that the fibrils cause problems in blood vessels, which can increase the risk of hemorrhagic stroke. But is Alzheimer's even a prion disease? Would the same thing occur in Kuru? I have not read of any hemorrhagic strokes under the symptoms for Kuru. So how would these prions affect a person's brain exactly in Kuru? What do they do to the nerve cells? I'd really appreciate help in this matter from someone who is well versed in the subject.
13. ## Why is it bad to prescribe antibiotics for viruses?

I know that antibiotics have no effect against viruses, but why do many microbiologists often criticize doctors who do so, apart from the reason that I have given above?
14. ## Dating

I guess she wasn't really your best friend eh?
15. ## Dating

Hmm...it's wierd... Herme3 hasn't replied in a while. He's probably in a coma.
16. ## Dating

Love is crap.

19. ## Dating

I guess you will. If she is in shock and a coma, then you should fall into shock and coma too. It helps to numb the pain.

22. ## Dating

Trust me herme3, they are right. Girls get very creeped out when you send them a letter. I frankly have no clue how you'd go about telling a girl something without her getting very creeped out and wierded out. Possibly because I am a very creepy guy in reality. But anyways, I am not going to bother reading through the entire however many posts there are in this thread, so do you mind giving me a short synopsis of the events?

Lol, good one Ecoli. Sadly, even Google doesn't help in this regard. One of the first four hits that came up was this topic.
24. ## Structural and Civil Engineers

Ahh, I see! What exactly does an architect do? Do you have to be a very artsy sort of person to be an architect?
25. ## scratch marks after sleeping

I agree with Blike. The first thing that came to my mind, after I read your post, no offence, was: sensationalist
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