Dimensions Definition and 1000 Threads

I read this article: http://www.sciencenews.org/view/generic/id/338500/title/Crystals_may_be_possible_in_time_as_well_as_space What dimensions is the article talking about? Doesn't everything have a fourth dimension, time?

I'm not sure if I'm posting this in the right place, but either way I was doing some research earlier and I came across a theory that I hadn't heard of before, and it came out in the early 2000's. And that's Moving Dimensions Theory, and from what I read it unified relativity and quantum...

I'm worried about the process of solving this problem, can anyone help me? We are to make a rectangular box, including the top, that has a volume of 144 cubic inches and for which the base is twice as wide as it is deep. The bottom, which must be strong, is made of a material that is three...

In 3 space dimensions consider a 1D string under tension between two fixed points. Let the string lie at rest on the z axis between z = 0 and z = ∞. We can produce linearly polarized and circularly polarized waves if I move the end of the string properly? Now if we add an extra space dimension...

This isn't really a 'problem', I'm just trying to follow Feynman's reasoning in section 18-2 of Volume 1 The Feynman Lectures on Physics. I've attached a png of the paragraph in question. I have 2 issues with this: 1. If the length OQ = OP, how can there be a right angle at P(x,y)? 2. I...

Reading the February edition of the New Scientist (about space-time being possiblly quantized in its own right) I read that the event horizon of a black hole is a 2-dimensional entity that may possibly encode all the information to describe the 3- 0r ->3 dimensional universe inside. That is...

The universe appears to have three space dimensions because of our size. The smaller an object is the less dimensions it has. If we where 4th dimensional beings we would probably be millions of miles in height looking into the known solar system with a microscope as if it was a marble. Time is...

1. Say you have a linear transform from A to B, and where A has a higher dimension than B. How do you show that the kernel of the transform has more than one element (i.e. 0)? Also, if B has a higher dimension than A, then how to show that the transform isn't surjective? 2. The attempt at a...

Homework Statement A heat-seeking missile is located at (2,-3) on a plane. The temperature function is given by T(x; y) = 20-4x^2-y^2. Find the equation of the curve along which the missile travels, if it continuously moves in the direction of maximum temperature increase. Express your...

Homework Statement Hey guys, so here's the problem I'm given: You are watching an archery tournament when you start wondering how fast an arrow is shot from the bow. Remembering your physics, you ask one of the archers to shoot an arrow parallel to the ground. You find the arrow stuck in the...

Homework Statement A metal can which holds 450 cm^3 is to be manufactured in cylindrical shape. The top and bottom will be cut from two squares and the corner scrap discarded (but paid for). The metal for the sides costs 0.1 cents/cm^2, while the cost for the top and bottom is 0.15cents/cm^2...

Can dimensions exist that are neither spatial nor temporal?

Homework Statement A watercraft with an initial velocity of 6.4 m/s [E] undergoes an average acceleration of 2.0 m/s2 [S] for 2.5 s. What is the final velocity of the watercraft?Homework Equations vf = vi + a * t a = v / t v = v2 + (-v1) pythagoras and cosine law? The Attempt at a Solution I...

On the arbitrary idea of some String Theorists that some dimensions are "small". [Disclaimer: I'm not an expert; a genuine question on basic notion of the theory follows, pardon the excitement:] I don't get the arbitrary idea of some String Theorists that beyond the 3rd/4th dimensions the...

I've heard there's no up and down in space due to the absense of gravity. So does the mean that outer space just has two spatial dimensions?

First post! I'm investigating chaos in non linear coupled spring oscillators. After generating a poincare' map of said system i wanted to see if the map was fractal. i proceeded to use a box counting method in order to calculate a fractal dimension. I generated a plot of log(number of...

Homework Statement First of all, sorry if this isn't the right place to post this. Four points A, B,C and D have coordinates (0, 1, -2), (1, 3, 2), (4, 3, 4) and (5, -1, -2) respectively. Find the position vectors of a. The mid-point E of AC b. The point F on BC such that BF/FD = 1/3 Use...

Hi, I don't think my textbook gives much information on vectors in 3 dimensions. The first chapter is on vectors, but only uses 2 and 1/2 pages to explain vectors in 3 dimensions. I have found a wealth of information on vectors in 2 dimensions (there are literally hundreds of detailed videos...

I don't really know much about GR, but I was just wondering about this theoretical question. I am asking this, because I think Special Relativity is a theory of four dimensions, and wasn't sure how many dimensions GR involved.

Homework Statement See attachment Homework Equations The Attempt at a Solution I'm not sure how to determine which points are co linear or which point lies in between the two. My book doesn't discuss how to do this at all. but PQ→ = <1,-1,2>, PR→ = <3,-3,6> I believe I found...

Homework Statement a baseball with a mass of 0.152 kg is moving horizontally at 32.0 m/s [E] when it is struck by a bat for 0.00200 seconds. The velocity of the ball just after the collision is 52.0 m/s [W 20 N] a) Find the impulse experienced by the ball b) find the average net force of...

I've just been thinking about moments of inertia in n dimensions and I just want to establish if this makes any sense: I'm considering doing a Monte Carlo evaluation of the moment of inertia of any n-ball - a solid sphere in n dimensions. Now I think you can say that the moment of inertia of a...

Hello, I have a question, please let me have your answer, if possible: In a space with an extra spatial dimension , where the extra coordinate is compact: 0 \le y \le 2\pi \alpha And the metric of the space is: {G_M}_N = \left( {\begin{array}{*{20}{c}} {{g_\mu }_\nu (x)} & {{A_\mu }(x)}...

Hi, Calculate the dimensions of a solid rectangular beam using the information below: Max Bending Moment= 8280Nm Ze = 36cm^3 Allowable Stress = 230MPa d = 2b Stress = moment/section modulus

Homework Statement Find the centroid of the region D, lying above the sphere x2+y2+z2 and below the paraboloid z=4-x2-y2. Homework Equations The Attempt at a Solution I decided it might be easier to change it to polar coordinates soo I did M=∫∫∫ dzrdrdθ where z goes from...

Hi everyone Homework Statement At first I want to find the langrangian function and the equation of motion for a system which exists of 2 masses(m) coupled by a spring(k). It's moving in 3 dimensions.We shall use cylindrical coordinatesHomework Equations LangrangianThe Attempt at a Solution...

Homework Statement find the components of the velocity of a car that is moving 10.0 km/h in a direction of 35degrees north of east Homework Equations The Attempt at a Solution

Hi! I'm a bit stuck with this special relativity assignment, here's is the problem: So the problem here is that not only does the hole shrink in S', as stated in the problem description, the pole should also be wider by a factor of 3 in this frame. So we have an 18 ft wide pole that has to...

What Higher Dimensions "Feel" Like nevermind.

Curl is easy to compute in 3 dimensions and if you let the third component be 0, its also easy in 2 dimensions. If you let the second and third components be 0, it is also easy in 1 dimension. My question is, is there a generalisation for curl to n dimensions and if there is, what is it and is...

My teacher said e2 c x ħ/R Where e is the electric charge, c is speed of light and h is reduced constant and R is radius. My teacher said this has dimenions of energy, is this right?

I tried googling this first and of course looked at my notes but the questions asked pertaining to dimensions were confusing me more so I thought I'd ask directly. Sorry for asking the same question I'm sure someone else has asked. Okay. So, to find the dimension, do I first make sure it's a...

Maxwell's equations use four dimensions. But wouldn't we need more dimensions to completely describe the EM force. I'm thinking of polarization and twist. So how many mathematical dimensions are necessary for a complete description? That is, how big do the matrices need to be and how many...

Can anyone tell me that how many dimensions are there in a black hole and which are the dimension

Homework Statement A 1300-kg car collides with a 15,000-kg truck at an intersection and they couple together and move off as one leaving a skid mark 5m long that makes an angle of 30.0° with the original direction of the car. If μk = 0.700, find the initial velocities of the car and truck...

If energy/matter deforms spacetime in three dimensions... Then why do we get galaxies in (relatively) flat discs and black holes that emit radiation in a single plane?

A golf ball mass of 4.7 x 10-2 kg is hit by Tiger Woods and drops exactly into a hole 100 meters away. It is observed that the angle between the initial velocity vector and the horizontal plane is 30 degrees. What is the magnitude of the initial velocity? Isn't the problem missing...

I have just a quick question I was wondering about and I was wondering could someone answer it here. Is it true that for example the third dimension is composed of an infinite number of 2 dimensional planes on top of each other which give rise to width, the third dimension? If this is true...

I have just a quick question I was wondering about and I was wondering could someone answer it here. Is it true that for example the third dimension is composed of an infinite number of 2 dimensional planes on top of each other which give rise to width, the third dimension? If this is true...

Homework Statement "An object from the surface of the Earth with the escape speed ve can move infinitely far from the Earth. The escape speed is independent of the mass that is trying to escape and only depends on G, the gravitational constant, ME the mass of the Earth, and RE the radius of...

Homework Statement At t = 0 a batter hits a baseball with an initial speed of 29 m/s at a 55° angle to the horizontal. An outfilder is 85 m from the batter at t = 0 and, as seen from home plate, the line of sight to the outfilder makes a horizontal angle of 22° with the plane in which the ball...

Homework Statement Homework Equations A 50 lb force is applied to a corner plate as shown. Determine an equivalent system consisting of a 150 lb force at B and another force at A. The Attempt at a Solution There is an algebraic solution to the problem, but I was wondering if it...

Homework Statement I am trying to calculate the (Vo) for a ramp length from a horizontal decline marked at 20 cm. The ramp on top of a table has an angle of 41 degrees. I performed 3 trials releasing a ball bearing at the 20cm mark and averaged 53.3 . The table height is 87.3 cm. Isn't Vo...

Homework Statement Using your understanding of projectile motion along with some background research on video analysis, devise a way to find the initial velocity of the tennis ball in the video just as it enters the bottom left of the screen. There is some important information for you to...

We usually describe angles in two dimensions (x and y plane). What is the mathematics behind three dimensions?

Homework Statement We wish to find, in 2+1 dimensions, the analogue of E = - \frac{1}{4\pi r} e^{-mr} found in 3+1 dimensions. Here r is the spatial distance between two stationary disturbances in the field. Homework Equations In 3+1 we start from E = - \int \frac{ d^3 k }{(2\pi)^3}...

Recall that A can be broken up into its components x,y, and z. Can You simply add more components to describe any number of dimensions. Where n would be nth dimension? A=A_x+ A_y+A_z+⋯A_n

Homework Statement Homework Equations \int\vec{E}\cdot\vec{dA}=\frac{Q_{enc}}{\epsilon_{0}} \int\vec{E}\cdot\vec{dA}=\frac{Q_{enc}}{k\epsilon_{0}} V=\int\vec{E}\cdot\vec{dS} C=\frac{q}{V} C_{eq}=C_{1}+C_{2}+... \frac{1}{C_{eq}}=\frac{1}{C_{1}}+\frac{1}{C_{2}}+... The Attempt at...

hi I am doing project on piezoelectric energy harvesting which is a cantilever structure using COMSOL. I have some doubts related to my project. I designed cantilever structure having three layers substrate (SiC), piezo (ZnO) and electrode (Al). My doubt is that when piezoelectric layer...

Hi there all, I'm new to this forum and I really need some help. The question is described as follows: Estimate the maximum "initial velocity" that you can achieve with a regular tennis ball. Presumably there are no variables, nor are there any equations involved. I think that an...