In common usage and in philosophy, ideas are abstract concepts. Also in philosophy, ideas can also be mental representational images of some object. Many philosophers have considered ideas to be a fundamental ontological category of being. The capacity to create and understand the meaning of ideas is considered to be an essential and defining feature of human beings. In a popular sense, an idea arises in a reflexive, spontaneous manner, even without thinking or serious reflection, for example, when we talk about the idea of a person or a place. A new or an original idea can often lead to innovation.
Under what general formal mathematical conditions does an analogous idea of energy exist and satisfy conservation? In a gradient vector field, energy as force times distance exists and is conserved in some sense. What is a more general idea? What, conceptually, makes energy "energy"? Is...
My school having a physics project competion and I don't know waht to do ,can anyone give me some idea or tell me where can i find the physics project tutorial at the internet . I am a pre-U students(similar to A-level) ,I want to do a more interesting project .please elp me .
so i was in the Dining Commons today, and they had some corn bread squares at the dessert station. at first glance, they looked a bit like rice crispies treats, and i got all excited. upon further inspection, i realized what they really were and became thoroughly dissapointed. then i looked...
Canada's supreme court decided this week it was okay for Sikh to wear their ceremonial Kirpan to school. They were judged to be no more dangerous than baseball bats or scissors, though they remain banned in airplanes or courtrooms.
The religion is about 500 years old, originates from...
My god, is it just me or has every single episode of this guys show lately been about child predators?!?
Kinda scary to think there's so many perverts out there... or well, am i allowed to call them perverts? Not "misunderstood"?
So I was enjoying breakfast this morning, very early like (at seven or so), and I was looking at my coffee mug, and also at a glass of grapefruit juice. So I thought, why not? and toppled the contents of one into the other. And the result was suprisingly sweet-tasting, lemony, coffee-ish, in a...
I was thinking about perpetual motion and perpetual energy generation when I got to thinking about magnets. Now, for the record, I don't think this would really work, but I can't think of why not, so maybe you guys can educate me on this.
Open the attached image to look at while you read...
What's going on here? It doesn't seem like it would work well at all. I remember popular science said something about how little power it produced. Reminds me of a Carnot engine. http://en.wikipedia.org/wiki/Carnot_cycle
Is this a good idea, or should I stick with nuclear fusion reactors?
Hey, would it be possible to attach hydrofoils onto a kayak---to have the padder row about a foot or more above the water level? Or have the entire kayak elevated above the water level?
Then again, would the weight of the kayak and the paddler be too difficult to offset? (Though, I currently...
i have a flat box in which i put a spinning beam hold by the center
i putweights on the beam that can run longitudinally on the beam so when the beam spins the centrifugal force send them away from the center
i tight a cable to a corner of the box and the weights in such a way that when...
Hi all
So-called "free trade" is one of the holy grails of capitalism, is it not? And the USA takes the lead in creating and defending free markets? How, then, does one explain this?
Just one example of 'capitalist freedom':rolleyes:
This is just the tip of the iceberg, of course - if...
So I got my calc 2 final this week, and I'm doing it in leau of doing a calculus project. In case I fail the test too hard, I'd like to see if I can get a project done before the semester ends.
The project involves going out and finding a business that could use calculus to make something...
For my Anatomy class, we are requiered to do a science fair project. I am having trouble coming up with an idea but I think I want to do something involving acid-base reactions. I would appreciate any ideas on this topic. Thanks.
I'll be starting grad school next year, and I'm already starting to worry about the qualifier ;) While poking around on Barnes & Noble's site I noticed that there are whole books which are just collections of problems in physics, with and without solutions. I thought that these might be a...
Hey guys.
I have a lens problem:
A lens has a power of 300 dipoters, and a radius a of 2 mm. An object is located just beyond the focal length to get high magnification. The space between the object is filled oil with an index of refraction 1.4. Estimate the resolution for 500 nm light...
A stuntman whose mass is 70 kg swings from the end of a 4.0-m-long rope along the arc of a vertical circle. Assuming he starts from rest when the rope is horizontal, find the tensions on the rope that are required to make him follow his circular path,(a) at the beginning of his motion, (b) at a...
I've had this idea for a while. I can't see anything wrong with it. Maybe someone here can tell me if it's unsound.
The idea is based on the dimpling of a golf ball. To my knowledge the dimpling of a golf ball reduces air friction and let's it go farther. I even heard of someone dimpling a...
I've got an idea for a science project that I thought I'd run by you. I was walking home one day in the rain and I thought to myself, would I get more wet if I walk or run? At least initially I plan on ommiting wind... if I can get a handle on it then I'll add this to the mix.
There are some...
i know the solution to a system of trhee odes of the form
div(xy)= C1 (1)
xy grad(y) = -grad(z) -C1y (2)
div(xy(y^2/2+ C2 z/x))=C3 (3)
where x, y, and z are functions of r only, (spherical simmetry) and div F= (1/r^2) d (r^2F)/dr, and...
In Goldbarz thread, CarlB voiced this idea:
this is a possible response to Fermi's question "where are they" or to the apparent Silence. what's your reaction?
BTW it is not as optimistic as it sounds right off because he just says "be able" and we might have the potential but fail to do...
how do i get to solve this integral,i have no idea whatsoever so no one should expect what i have done.it was presented to me by a colleague
[x^(1/x)]^[x^(1/x)]^[x^(1/x)]^[x^(1/x)]^[x^(1/x)]^[x^(1/x)]^[x^(1/x)]...
Lets imagine that there is a gravitational field and you are in a position that if you fall a meter your g increases by 2m/s/s (I'm pretty that that's possible). In this case, the more you fall the more P energy you get and you get more K energy. In order for this not to contradict the...
I'm just curious to see what other people in this group have to say about this theory I have. I used to think that time was the fourth
dimension. It seemed pretty logical due to the way dimensions are built up. The zero dimension is a point, the first dimension is an
infinite number of...
What do you consider to be the basis or roots of your political philosophy and opinions? Is it Plato, the plight a certain group like the Palestinians, a cause such as environmentalism, national loyalty and basic patriotism, a greater concept or ideal such as world peace, an economic ideal, or a...
I'm having a bit of a hard time getting my head around this idea. Can anyone provide some links to good references, or offer an explanation here? Thanks.
If you are in the US, or have access to Public Broacasting Station signal, you may want to mark your calendar or your TIVO for Oct. 11 next week.
http://www.pbs.org/wgbh/nova/einstein/
Zz.
You know the awkward person who says he/she doesn't want anything, but
you know they do well for a novel gift i thought why not treat them
to this.
http://www.braceface.com/medical/Pages/Trepanning.htm
http://www.trepan.com/_index.html :biggrin:
define L[u] = a \frac{\partial^2u}{\partial t^2} + B \frac{\partial^2 u}{\partial x \partial t} + C \frac{\partial^2u}{\partial x^2} = 0
Show that if L[u] is hyperbolic and A is not zero, the transofrmation to moving coordinates
x' = x- \frac{B}{2A} t
t' =t
takes L into a mutliple...
determine the inital velocity of a projectile that is luncked horizantaly and falls 1.5m while moving 16m horizantaly
i tried everything all i figerd out is that they r displacmednts the accelaration is 9.8 and nothing i don't have enogh info to do anything
please help me
surely building a craft to go to Mars without any infrastructure is pretty pointless & will end up being as beneficial as the moon. Wouldnt developing a petrol station in orbit be a better idea, and then a interplanetary ship that doesn't land but stays in space & a way to get up & down to it...
Hi all,
New member here, found the forum when lurking around the 'net last night.
A very brief disclaimer: I've a Chemistry degree, I work with computers in the IT security field, but I am NOT a Physics expert... far from that.
I've read a lot of "popular" literature, and from my humble...
You can name more that 1 person and add more of your own. o:)
1)witty:
2)humorist:
3)kind:
4)cute:
5)helpful:
6)thoughtful:
7)wise:
8)hot:
9)cool: :cool:
10)strange:
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Threadholic: Mr Wolram, yomamma
Gentleman: TSA, Astronuc
People tell me I should, I say why? I figure if my body doesn't tell me to eat then I won't (unless loss of appetite from illness or something). When I'm sleeping I hardly lose any energy, just my brain, stomach, and heart!
I usually end up eating it more often than not, but I do NOT like...
I have this problem here.
Let's say: A plumb bob does not hang exactly along a line directed to the center of the Earth's rotation. How much does the plumb bob deviate from a radial line at 40 degrees north latitude if we assume that the Earth is spherical?
I was thinking about creating a blog that would make regular posts about what a particular physicist does. The aim would be to provide a resource that would show how diverse the areas of physics study are, give details on what physics is being done and provide a little insight into what...
I don't know if this would work or not.
What if you used one engine bay of an F-15 for a scramjet, the other for an SR-71 engine. That takes you to mach 10 and the edge of space. If you strapped PAM rockets to the missle racks on the wings and belly, could you make it to orbit velocity...
I would like to clarify that this idea that mass increases at relativistic speeds is an explanatory tool only (usually to explain why you cannot exceed the speed of light). It comes from the fact that in some equations, the factor gamma = 1/sqrt(1-v^2/c^2) multiplies the mass. However, I think...
This thread is an offshoot of https://www.physicsforums.com/showthread.php?t=83978&page=1&pp=20.
Hmmmm, OK...
ex·pand
v. intr.
1. To become greater in size, volume, quantity, or scope: Air expands when heated. This critic's influence is expanding.
2. To speak or write at length or...
Well to begin I should say that I used to be a caffeine freak. I averaged 2L of Diet Dr Pepper everyday for the past four years.
About three weeks ago I ran out of pop and, being extremely busy with college, I was unable to get to the grocery store for anything other than a few bags of food...
tempting idea, but crap?
The universe is quantum mechanically. But no one understands quantum mechanics, as Feynman put it.
On the one hand the pivotal role and accuracy of QM in describing nature. On the other hand the inability to interpret QM (1. quantum reality- what is a superposed state...
Sometimes on PF people use words and phrases that CAN seem aggresive without smiley faces or similar to 'disarm' them.
However, as an alternative, we could use 'different' punctuation' to really be aggresive, without anyone knowing actually knowing, so also avoiding upset!
Here, take a...
Consider some hypothetical universal rule which everything (including nothing) must satisfy. Then take that some hypothetical object that does not satisfy this axiom. What can be said about that object? Certainly it can not be said that it doesn't exist.
In following up one of my idiot ideas that usually turnout to be absolotley stupid, I may have discovered, or rediscovered, an actuall result that I think might be worth publishing in arxiv. Since I am only a undergraduate student I am wondering what I should do. Should I talk to a doctor at my...
Don't know what forum to put this in.
In what must be the most retarded step I know, we have been told to hand in a report in a "decorative container" worth a mind bogglingly large percentage of the mark.
Considering my report is on the anthropic principle and its relation to cosmology...
First I called it an idea, not a theory. One might call it an hypothesis, though I do not think it is at that stage. I have posted it so someone who works on demminsions can help see it, maybe test it.
To start off with, the string theory says that there must be 11 deminsions. I know this...