Shapes Definition and 157 Threads

Hi all, Is it possible to determine the volume of a shape where, in the x and y dimensions, the shape is described by an equation, and then its elevation is described by another equation? An example would be a parabola in the x-y plane whose elevation is based on another parabolic...

A Thousand Kilobots Self-Assemble Into Complex Shapes http://spectrum.ieee.org/automaton/robotics/robotics-hardware/a-thousand-kilobots-self-assemble https://www.youtube.com/watch?v=G1t4M2XnIhI

Hey guys, I would really appreciate some help for this question I'm stuck on at the moment: "A piece of 2 m long wire is to be cut into two pieces one of which is to be formed into a circle and the other into an equilateral triangle. How should the wire be cut so that the total area enclosed...

Good Morning everyone.. Has there been discussion on here regarding alternate shapes for compressed air cylinders (+3000 psi) I know why compressed cylinder are the shape they are, but in this day and age of science & technology, why are we still using round cylinders? could one not design a...

I apologize if this is the wrong forum but I need access to mathematicians who know what's happening with polygonal math. I created an unproven algorithm (or heuristic) back in 1999/2000 for bounding shapes with polygons. It was interesting because it was fast, general for polygons of any...

So, I don't like calculus class, since it's very boring, but I do like math, and I intend to sort of become a mathematical autodidact. So I just thought I'd try to come up with a solution to a problem I created, and this was to integrate one of those gigantor Reese's easter egg things (holy...

In the following video, the physicist says something about the mathematical number of a shape at 2:49. There's a mathematical number for shapes?? That's beyond interesting. Could someone please give a somewhat simple explanation? I'm only in introductory physics but was told this is more...

Is it possible to predict, at least in theory, which shape a crystal of some combination of atoms would have. If so, what are the principles for such a calculation. I have seen a theorem in classical thermodynamics called wulfs theorem about the equilibrium shape of crystals. Does this explain...

Homogeneous beam shaped in letter L is suspended on two ropes of the same length l. The beam is of negligible thickness and its longer arm is three times longer than the shorter arm. Its overall length is l as well as the length of one rope. Look at each situation in the figures. How can I...

Sorry, this isn't a question from a book or something, but I wasn't sure where else to put this. Is there a convenient way of memorizing or deriving the following?: I have an exam in a week and I thought I might as well try asking before making flashcards.

BMW has a kidney shaped grill for the air intake but the front looks weird from the side.Looking at a M3 inline-6 from the side,the front seems so long.This brings me to my question,how do engineers arrive at the front lateral cross sectional shapes of cars? I assume that the front lateral...

Homework Statement Number 17: http://i.minus.com/jbqSc694thPeBA.jpg Homework Equations I'm not even sure where to start. The Attempt at a Solution I know that tetrahedral shapes are non-polar if all of the attached elements are the same (e.g. CH4 or CCl4). I know all the answer...

As a means of curiosity, I am working on a problem involving the rotation of various shapes. The thing that I am interested in is the cross-sectional length of the shapes as they cross the x axis. So imagine that you have a circle with a pivot point at its bottom. You then rotate it about the...

Archimedes principle of the force of upthrust = weight of water displaced by the body immersed , but is this law independent of the shape of this body. If we use the idea that the upthrust = P*A on the lower side - P*A on the upper side , if we use it on a rectangle or a square , the only change...

in the figure, the area of the interior of the rectangle represents set A, the triangle set B, the circle Set C, indicate the area represented by a. $\displaystyle A\cup B$ b. $\displaystyle A\cap B$ c. $\displaystyle A\cap C$ d. $\displaystyle B\cup C$ e. $\displaystyle \left(A\cup...

The problem is posted here: http://nrich.maths.org/5673 I tried subbing in values to get the biggest area: perimeter ratio possible. I used an arbitrary value, 12, for perimeter. For the triangle, I took out the hypotenuse and so A = 1/2(x)(y) where x+ y = 12. Its area is biggest when x = y = 6...

Homework Statement refer to question image Homework Equations refer to question image againThe Attempt at a Solution refer to working out image This is my brothers maths homework. He normally doesn't use online methods to request help and this is his first time.

Homework Statement Three uniform objects: a ring, a disk, and a sphere all have identical masses and radii. They are released simultaneously from the top of a ramp 3.80 meters in LENGTH. If the ramp is inclined at θ= 17.0°, use conservation of energy to calculate the linear speed of the ring...

I am attempting to use integration to determine the formula for the volume of three dimensional shapes for the sake of practice. My issue is I really lack the skills to determine what type of two-dimensional rotations will obtain a shape. The only one I have been able to do so far has been...

Hello, I might be wrong. Please correct me. In planetary motion or in the size of galaxies: (a) The gravitational attraction of a body, say sun and the force from other planets, creates the elliptical shapes, right? (b) If the gravitational force of anyone body is high than the other...

I'm not electrical minded but I am wondering why my guitar pickup like most have the these rod shaped magnets. Why are they that shape and why is it important? I would like to make my own pickup to understand better how it functions and to see if I can achieve the attempt in making one...

Why does mathematics deal with the world of perfect spheres, triangles and squares. I understand how this can be applied to architecture and engineering. But this seems counter-intuitive to 'nature' that surrounds us which is objects that are not perfect in shape. The Earth for instance isn't a...

I know that the shape of s orbital is sphere, p orbital is dumbbell shaped and d orbital is like a doughnut but why do these orbitals have these shapes why not some other shape.

do you see in that photo how that little stick of ice shoots out from the top? What do you think caused that?

I have a process that requires an operational profile that follows one of the curves in the diagram which follows. I wish to program into the device a general equation that will give me a family of curves of this general shape. The goal is to adjust the parameters of the equation so that I can...

Homework Statement Consider the two-dimensional spacetime with the line element dS2 = -X2dT2+dX2. Find the shapes X(T) of all timelike geodesics in this spacetime. 2. The attempt at a solution I have the solution to this problem but I don't understand one step. For timelike worldlines dS2 =...

Homework Statement Apply the principle of superposition to draw the resultant shape when each of the sets of pulses shown interferes. (Draw the diagrams so that the horizontal midpoints of the pulses coincide.) Homework Equations Please check this website...

The leads on giant capacitors have always looked mysterious and complicated to me. They almost look like RF cavities to me. Why are the bushings the shape they are?

If I have a cylinder with a radius r and an axis that passes through point b with the direction of vector n, show that its equation can be written in any of the following forms: 1) ||(p-b) X n|| = r 2) (p - b) X n = r.e (where e s ia unit vector orthogonal to n) 3) ||(p-b) - ((p-b).n)n|| =...

I have never been able to grasp why certain mode shapes are the way they are. For example, I ran a free vibration analysis on a vertical beam fixed at the ground. The second mode shape is vertically straight. This is the same case whether or not I have a lumped mass at the top of the beam. Any...

Hi, I have a program that draws four rectangles at a time using a while loop. this is my code. [code = java] import java.awt.BasicStroke; import java.awt.Color; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.event.ActionEvent; import...

Why are the bonds in sp3d hybridisation of different length? And why sp3d2 has bonds of equal length. For me sp3d should also contain all equal ond lengths with a symmetrical shape but it doesnt. Why not?

Hello everybody, I have a shape (polygon) made up from pixels (squares) similar to the image below. I need an algorithm to cut it into "lines" i.e. shapes of 1x[1..20] pixels. The lines should not be necessarily straight, but they should fill the entire area. Any ideas on where to start...

Hi I am using Ansys to find the natural frequency of a structure but this has meant that my understanding of vibrations has become unstuck. When I last studied natural frequencies, it was under free vibration. I formed the impression that one structure can have only one natural frequency...

Homework Statement Give a formula for a function whose graph is described. Sketch it using a computer or a calculator. A cone of circular cross-section opening downward and with its vertex at the origin.Homework Equations I know how to draw the cone and the properties of a cone, so that's not...

I'm studying for a re-examn in a physical measuring techniques course that includes some Fourier analysis. On old exams there are always a question about a graphical 2d Fourier transform. It can be an ellipse containing a grid of circels, or something like that. In the solutions he takes the...

Hello, I'm trying to research a method or algorithm to determine how to best fit a couple of diferent shapes into a given area. Type of area: Rectangular Types of shapes: Rectangles, Triangles, Circles Where I work at we have to figure out how to best arrange the shapes we need into a...

How could "strange shapes" affect space-time? To my understanding anything massive enouph to bend space and time noticeably would end up becoming a sphere due to how gravity works. But what if you could have diffrent shapes that were massive enouph to affect the universe? What if you made a...

I'm currently trying to cram knowledge of the transition metals into my head for a chemistry final exam, although i have come across a stumbling block when reading about the 3 dimensional shapes that complex ions form. My textbooks say that complex ion with 4 coordination bonds will form a...

I'm basically just trying to find a list of all the shapes and their relative moment of inertia to each other. I want to see what shapes have more and what less, just to get a more intuitive sense to this subject. Does anyone show such a list, or maybe can just tell me of basic geometrical...

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...

Homework Statement http://img857.imageshack.us/img857/3200/thedrawing00.jpg In a rectangle ABCD a square is built, EFGD, and a right triangle BMF, as described in the drawing. Given: DC = 60 cm BC = 40 cm The sum of the area of the square and the triangle is 784 cm2 Calculate...

In chemistry and biochemistry, what do the hexagons with letters in between them mean? Call me silly but for some reason they never taught this to us in school.

Homework Statement Model the above beam with 3 elements(image provided in attachment). Calculate and list the first 6 natural frequencies Plot the mode shapes corresponding to each of the natural frequencies Homework Equations DET(M^{-1}*K + [I] \omega^2)=0 shape functions...

Can anyone help me please? Are they all elliptic or just some? I need to know for planets, comets, moons and satellites All help greatly appreciated.

I have looked around several internet Physics sites and information sources, and even asked questions here and in other places, and can't seem to find answers to my questions about a thought experiment I came up with: Think about three similar cases: A ball, a solid cylinder, and a hollow...

If the light viewed through a telescope from one end of a specific galaxy takes, say, 100,000 years longer to travel to the eyepiece than the light at the closer end of the said galaxy, why isn't it skewed? Same goes with everything in the cosmos, why isn't more skewed the further back we look...

For the equation: contact stress = {(1 / (pi[((1-v1^2)/E1)) + ((1-v2^2)/E2))) ^ 0.5} * {((Fn/b) * (Sum (1/pi)))^0.5} Where Sum (1/pi) = [(1/p1) - (1/p2)] for concave shapes in contact with convex shapes Sum (1/pi) approaches 0 as the two radii get closer, however when the two radii...

This is just a curiosity question. Are there lens shapes different than just conic sections? Any research or any found applications?

First post, I am just a layman, so go easy. The way I understand it, the moon is following a straight line through space. However, the mass of the Earth is so great that it warps the fabric of spacetime and it appears that the moon is going around the earth. Same with any moon or planet, they...