Shape Definition and 638 Threads

Homework Statement I need to find the bending moment of a washer shape for a project I'm working on so I don't have an exact problem statement. Imagine that a washer was fixed (not pinned) around its inner radius and a force were applied evenly around the outer radius. How can I go about...

Hello all, I've posted an image below of a very basic maths question I can't seem to solve. Even after looking at the correct answer I cannot seem to figure out how they got it no matter what I try. The question is: http://img684.imageshack.us/img684/6179/mr2q19.jpg From what I can...

Can intense harmonic vibrations cause an object to change shape to match the source or take that shape if it is plastic?

I'm wondering if there's a term for the property of spheres that makes gravity pull equally on all aspects of the sphere's mass. The wording for what I'm asking is tricky, so I'll give an example of a shape that wouldn't have this property, a long prism. If you drop a long prism on an angle...

For a container made of glass, what geometrical shape of the container would be best for maximum Total Internal Reflection, given that light incident on it is coming after reflection from a concave mirror? My hunch is that a cylindrical shape of the container is best, but I was not so sure...

EDIT: I meant to place this in Engineering help. Would a moderator please move it there? Thanks. Homework Statement I need to work out the theoretical principle second moment of area for an L shaped specimen I have...

This is from Spivak's Calculus. In an appendix, he defines polar coordinates. One of the exercises in this appendix is showing that the lemniscate, whose polar equation is: r^2=2(a^2)*cos(2theta) is the set of points P that satisfy that the product of the distances from said point to two...

I was wondering why, when I arrange six cylindrical magnets, about 1inch long and 1/5th inch wide each (neodymium magnets) in a hexagon shape by arranging them into a chain of N-S-N-S-N-S (top or bottom... with the other end obviously being opposite in arrangement) and connecting them into a...

Homework Statement When a paper cake case falls right way up through the air it quickly reaches terminal velocity. The drag force ,D, acting on the paper cupcake case is given by D=fpAv2(v is squared) Where p is the density of air which is 1.2 kgm-3 v is the terminal velocity A is the cross...

Hi, Say you have a simulation of a nano particle resting on a flat surface of metals. It is described by the effective medium theory. How do you find the free energy of a face to be used in the Wulff construction. A suggestion i got was to use periodic boundary conditions in all directions...

Is the VSEPR model a tool to help us visualize what is happening to molecules, or do the atoms really take on the shape of something like a trigonal bipyramidal?

Hey guys. I am trying to find a shape that suits my needs. The amount of vertexes can be any, but the fewer the better. The edges are special in that each end has an A or a B. like this A------B I need the vertexes to have more A than B inputs from edges. I need all vertexes to...

Basic chemistry: sulphur dioxide shape??! I realize this isn't homework, but it's so basic I'm ashamed of putting it in the chemistry section. I'm trying to self-teach here, but my textbook is awful and I'm even worse. Question: Workout the shape of SO2. Step 1: Draw lewis diagram to work out...

Hi all Edit: The reflecting side is the right side of left slab Please look at the pic above ... The light from source splits at left slab and goes in 2 directions and come back to interfere. From figure, it is obvious that path diff. in slabs for both rays is 0 and only path diff...

Hi, I'd like to ask, if its possible to shape a fire. Would it be possible on tealight ? I don't want complex shapes just simple ones like sphere, cylinder... Thanks

Hi all. I'm looking for a paper that I've seen referenced in a couple of articles I've been reading. The paper is O. M. Kiselev, Determination of gas-bubble shape in axisymmetric flow of fluid, Zh. Prikl. Mekhan. Tekh. Fiz., No. 3 (1963). The English name of the journal is Journal of...

Homework Statement As part of a test I was given an irregular shape to find its centroid. It was a rectangle with a right angled triangle on its right side (I don't have a picture to upload for ye unfortunately). Homework Equations dA=y.dx X(bar)=intrecal x.y.dx Y(bar)=intrecal y^2/2.dy The...

I have read that at sea level gravity is the same everywhere on the surface of the Earth. I have also read that motionless clocks at sea level will stay synchronized. It seems to me that this should be a consequence of general relativity. If one instead uses Newtonian gravitation then...

Is the big bang (referring to the well-established theory of post-Planck time evolution) compatible with any model of a finite universe that isn't spherical in topology? It seems to me that the big bang theory requires that the universe be finite in volume and the only way that seems feasible...

The Image has all the details: http://img38.imageshack.us/img38/3448/question3p.jpg Uploaded with ImageShack.us I honestly I have no Idea as to where I should begin. Any hints on how to get started?

What is the shape of the string at time=0? This is my wave: y(x,t)=(0.03)sin( (3π/4)x)cos(200πT) I assume that x=vt and replace in sin. Then sin(0)=0 and then the shape of the string is a line. Is this correct?

I saw a shadow of a catenary (or close enough) on a cylinder and wondered about the shape. Specifically, it was a powerline strung between 2 utility poles, and the sun angle would have been around 45 degrees or so, and the cylindrical grain bin was between and north (I am in northern...

why is rainbow always an arc?

Why is the Earth not perfectly round

Hi Guys, Just a thought, if a job of a black hole is to suck everything in it's surrounding to nothing-ness. Then why are the there examples of black holes with jet streams flowing away from their axial poles? Apparently the Earth's gravity field is weaker at the equator, so why does...

Homework Statement A piece of wire 40 cm long is cut into two pieces. One piece is bent into the shape of a square and the other is bent into the shape of a circle. How should the wire be cut so that the total area enclosed is a (a) maximum and (b) minimum? Homework Equations Area...

Gravity around star is often depicted as the curvature if spacetime or a 'dimple" in a flat sheet. What would happen to space-time around a star if the star were to instantly disapear? Would the fabric of space time snap back to flat space or would it reverberate, expanding then contracting...

In Gamow's short book 'Gravity' he describes the effect of lunar gravity on the earth, in particular the seeming paradox that the oceans, in response to the tug of the moon, swell both in the direction of the moon and on the opposite side as well. He resolves the paradox by explaining that...

Is it shaped like a tornado, or a sphere, or is it flat like a disk? If there was a way to view a black hole, dimming the brightness around it to get a clear look, what would be its full shape if you could view all around the outside of it from every possible angle?

Why don't electrons move only along the surface of orbitals? Moreover, how do electrons move within orbitals, random movement or do they follow a definite path? In a p-orbital, does one lobe consist of only one electron? Why is the p-orbital dumbbell shaped and not spherical?

Found a really cool TEDTalk video. What do you think about it?

Does the equation of state of a gas of interacting particles depend on the shape of the container they are in? For instance, if the interaction force is gravity (a central force) and the particles are in a spherical container, then it seems reasonable that the pressure on the wall of the...

I'm having trouble imagining how an orbiting object would get distorted by tides --- in the first instance, say, the distortion of an initial uniform dense ball of coffee grounds (of the sort John Baez likes to imagine in his web pages). I know and understand why, if it were infalling radially...

So, suppose for visualization there are only two dimensions: ct and x. Now if the metric where Euclidean, we could visualize this space is a simple plane. What would be the shape of the "plane" when the metric is +1, -1 (Minkowski)? Is it somehow hyperbolic?

PVC End Plug and Tube shape retention under heat and force?? Hi, I'm Mai from one of the semiconductor company. I'm in charge in supplier quality enginnering. I have an issue happened in my customer side where, whenever they received the unit from us the unit will spill out from the packing...

I have read on some threads that there are other possible shapes for spacetime and I wondered could any of these spacetime shapes, or their change over time, affect our measurement of red shift? Also does the matter density at the location where a photon is emitted relative to our own...

http://img839.imageshack.us/img839/4557/imagegrn.jpg What is this shape called? I thought a "pentagon" but since all sides aren't equal it can't be

I'm a college student in New York and I've been doing some thinking lately. Although mathematics is unfortunately one of my weaker subjects, I was wondering what you all might think of this idea. I've been reading about black holes and looking at different ideas of what the universe may look...

why the projectile motion's graph distance against inclination angle is parabola shape? ...thank you

Hi all, Im new here so please be gentle. Whilst in the pub last night a game was started with spinning a coin. We got to the point where we could all spin the coin with our hands in a circle around the salt shaker, about 3cm diameter. We then moved on to the pint glass and achieved that...

Reading just enough to be dangerous concerning Riemann geometry, choices of geometry regarding the shape of the Universe, etc., and the geodesic mappings to different geometric models (flat, spherical, and hyperbolic), I have an unanswered question in my mind. Acknowledging the affect of large...

Greetings, I see graphs of the amplitude of a photon's fields over time, but no illustrations of the shape of the field at any instant in time. Are the fields confined to planes like they look in the graphs? Or do they extend in three dimensions like the field around a magnet? Thanks

I get this error and I don't know how to get rid of it... I declared the Shape struct typedef struct { int tShape; int centerX; int centerY; int sizeX; int sizeY; int color; int filled; } Shape; When I try to send a Shape struct called shape to a...

Hi, my first post here and I'm not sure I'm in the right place or that I use the proper terms so please bear with me. I'm a programmer by trade, and I'm working on a project whereby I need to arrive at the best fit for a set of 2-D shapes fitting within a larger shape. Mostly we're dealing...

I was looking around the skymap on google earth, and I saw a strange red shape, so I zoomed on it and found this, It looks like some sort of star and a red thing shooting some jet, but I have no clue, never seen anything like this in any of my books.

Homework Statement CALCULATE POSITIONS OF THE CENTROID OF THE SHAPE SHOWN BELOW GIVE DIMENSIONS FROM POINT O ALONG THE HORIZONTAL X-DIRECTION, AND THE VERTICAL Y-DIRECTION. [PLAIN]http://img402.imageshack.us/img402/738/unledgj.jpg Homework Equations The Attempt at a Solution I...

http://arxiv.org/pdf/1101.5974 The Link between General Relativity and Shape Dynamics Henrique Gomes, Tim Koslowski 14 pages (Submitted on 31 Jan 2011) "We show that one can construct two equivalent gauge theories from a linking theory and give a general construction principle for linking...

Hello my friends, I have this problem and would appreciate someones help: Determine all intervals where the following function is increasing or decreasing. F(x) = -x^(5)+(5/2)x^(4)+(40/3)x^(3)+5 Solution To determine if the function is increasing or decreasing we will need the...

And I know that I'm being extremely stupid in saying that. I know I'm mathematically wrong. Please convince me otherwise. It doesn't make sense to me that if I change the shape of something it can alter its area/volume. I always thought these remain constant. Is there any experiment that I...

Hello! I'm trying to get my head around general relativity at the moment...(!), and there's one aspect of it that's really causing me a lot of kerfuffle. I understand that in an appropriately sized local inertial frame, the laws of special relativity occur. On those scales the curvature...