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# lightburst

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If it does then it does

8

1. ## Work along a curved path

I don't know what a Force per unit length is. I googled it and it seems to be related to electricity. I already solved the problem using conservation of energy. The Work done by the wind was simply FD (Force times horizontal distance). I just prefer knowing a detailed solution is all so I wanted to do it in calculus. I mean do I need to learn new math here? My experience is limited to single variable calculus. I mean I know how to do some of the more complicated stuff, but as far as being useful all I have is single var calc. $F\int \cos\theta\; ds$ I tried to use the arc length equation s = r(theta), but the damn r is there when I want a D. I know that l(sin(theta) + sin(phi)) = D and you end up with (F/L)D dl and when you integrate you lose the L and end up with FD which is what I expect. I just don't know what F/L is.
2. ## Work along a curved path

Walk me through the math, please. I know the definition of Work along a curved path. I just don't know how I can apply it to this particular problem. My book isn't much help. (To be fair, this problem didn't even come from it) I figure I need to represent the path as a function (or a vector function). I thought P = <R cost, R sint> but that went down the drain.
3. ## Work along a curved path

I've been trying to compute for the Work done by the wind F using calculus. Haven't had progress at all. http://www.pennsbury.k12.pa.us/pennsbury/Staff%20Pages/Pennsbury%20High%20West/Paulson,%20Tim/Honors%20Physics%20Fall%202013/Resources%20and%20Links/Materials%20by%20Chapter/Chapter%206/Jane%20and%20Tarzan%20solution.pdf
4. ## Definite Integration (Physics problem, sort of)

I don't see why it wouldn't be possible to use t as a bound on the v side. I mean the bound and variables within the equation aren't the same thing, right? The bounds are just some constants, no? Also, they couldn't be the same end points because when you use, say the projectile motion/free fall equations, final velocity and time isn't the same and initial time = 0 and initial velocity isn't necessarily zero, no? hmm I guess it makes better sense if like the bounds of the left hand side is a function of t, as in v(t). Is there perhaps a proof/theorem/property/particular topic I could look up?
5. ## Definite Integration (Physics problem, sort of)

You are given F(v) = -Cv2, the force as a function of velocity, and you need to show that x - x0 = (m/C) ln(v0/v) where m = mass and C is some constant. My question is why and how does definite integration work when you have 2 variables? I mean I was able to finish the problem using this as I've seen it be used in the textbook itself and also some math books, but I don't really understand or know how it works. In calculus classes, and also my book, definite integration is done using 1 variable. I mean we do multiple definite integrations but that's only 'on one side' and 'one at a time' and I've never really been taught definite integration on different variables on 'both sides' of the equation. I feel like because the right side is being evaluated from 0 to t, the other side should be evaluated from 0 to t also.
6. ## How to draw a circle without PI and how to obtain PI without knowing what a circle is...

Want to find out Pi? Physically measure the diameter and circumference of a circle and do (circumference/diameter). As you get more precise measurements, you'll see that you're seeing more decimal figures of the constant irrational number we all know as Pi.
7. ## Atheism showing signs of religion. [Resolved-NO]

You assume that consciousness is something that is beyond 'brain mechanics'; that consciousness is not manufactured by the brain. You can play with high-level interpretations of scientific laws all you want, but the fact remains. You first have to prove that we are more than chemistry. Alternatively, capture that ethereal consciousness right after a person dies and transplant it and see if it sticks. Or just capture one at all.
8. ## Daedalus' Eighth Challenge

I'd like to see solutions, please. My try was a total failure. I tried getting an equation of a parabola (y - h = A(x - a)^2) where A was in terms of the two points...
9. ## Zombie Apocalypse !

*coughOnPiratebaycough* Pretty sick movie. hah pun
10. ## Time travelers caught on film.

Notice how the icons get smaller in the first vid. Plus, just square dots really. Second vid is just bogus. Could be any device and the iPhone was never that thick or small. I think this one of quite good though, but that's just me.
11. ## Time travelers caught on film.

Time travel and we still think AT&T and GSM phones? Come on. It's like the 1800s talking about future transportation and saying "Where is your combustion chamber?".
12. ## Time travelers caught on film.

Could simply be a mini-purse or a sunglasses case. I will call it odd when, some bench in a park, a person is sitting alone with a 'phone' on her ear with absolutely no reason to compel her to put her hands over her ears for a long period of time. Though given this scenario, it's still not absolutely definitive. Shady though. Furthermore, she actually has the 'phone' quite lower than her ear. Somewhere in her jaw. Given the angle of the 'phone' at, say, 0:09, and the assumption that it is a straight device, rather than curved, the device only reaches the underside of her ear and clearly not ON her ear as though listening.

Anyone?
14. ## At this day and age, what graphics card?

Obviously. But surely a GTX 460 is better than a GTS 450, or an 8300 GS vs 8800 GT. Just out of the assumption that the company markets them as such. 'How much' better one is from the other is a different story and needs better research but in general that's how you would go. I should have said 'per generation' and 'per company'. The logic doesn't also apply to AMD/ATI vs Nvidia because ATI has 'higher' model numbers for their gaming line of GPUs.
15. ## Who the hell has laid these damn eggs?

possibly a turtle? As far as I have seen, snakes make some sort of nest for their eggs and it's not really underground.
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