What is Spiral: Definition and 192 Discussions

I put this on mt web site. it shows a serial of prime numbers. Al http://www.maverickexperiments.com/PRIME/prime.html

Homework Statement The problem: the distribution of pressure of the left side of the circular cylinder Homework Equations ρ= the density of water γ=ρg P=ρgh circle O = a long wooden circular cylinder The Attempt at a Solution MY QUESTION: Please see the curve...

In this problem, I need to find the trajectory of a particle (as a function of time) which moves at a speed 's' but also turns at an increasing rate; angular acceleration α. The trajectory looks like a spiral which converges to a point. The particle has an initial position vector p and a...

by Ken Croswell One of our galaxy’s arms may do a full 360, upping the chances that our galactic home is a rare cosmic beauty. Full story---including an excellent map of the Milky Way---at Scientific American.

Homework Statement A red Archimedean spiral is fixed to the ground. An external motor turns a grey support clockwise at w, the support can only turn around itself. On the support there is one orange disk that doesn't turn around itself at start. A stem is on the support. That stem: - turns...

So electrons were suppose to crash on nucleus according to classical physics. I want to understand the dynamics of it. The basic idea is that it will slow down as it emit photons. But with what force and mechanism? I think the answer is related with Abraham-Lorentz force, but i see too many...

So I've been searching up "bevel gear" CAD tutorials, but all I can find is "Spiral bevel gear". It seems like the spiral version of the bevel gear is much more popular in engineering then the normal one one. But drawing a spiral bevel gear, and manufacturing it would be more complex and prone...

In many vortex's, the center has low pressure, from the center of a stirring cup of tea to the centere of a hurricane or storm system. I'm trying to crudely model how this might apply to the center of a spiral galaxy. If the behavior is similar, and the center has a low pressure void...

Hello! There is a parametric way of defining a spiral curve: z = a*t; x = r1*cos(w*t) y = r2*sin(w*t). Is there a way to define the thickness of spiral?

Hi All! the mathworld website http://mathworld.wolfram.com/SphericalSpiral.html claims that the loxodrome is given by the parametric equations ##x=cos(t) cos(c)## ##y=sin(t) cos(c)## ##z=-sin(c)## Why so? Now, as far as I can see, since the spherical coordinates are ##x=sin\phi cos\theta##...

I was reading a post on 'Starts With a Bang' where they were discussing the merits of Dark Matter over MOND and there was a picture of a large spiral galaxy with many starts in the field behind it. What struck me was that the background seemed to be in perfect clarity. There was no distortion...

The problem statement Form a formula to generate every value in the 10x10 square spiral shown above. Use the variables: x = the column of the cell, y = the row of the cell, s = the size of the spiral (in this case 10). The formula must work for any size of spiral, where s is the width...

Homework Statement The uniform 45.6 mT magnetic field in the picture below points in the positive z-direction. An electron enters the region of magnetic field with a speed of 5.29E+6 m/s and at an angle of θ = 30.1° above the xy-plane. Find the radius r and the pitch p of the electron's spiral...

Homework Statement This is not homework, I'd like to know if it is possible to find the pitch a log spiral knowing that at every round (2π) r grows by 535.5 times. For the little I know the equation should be just r = e2π = 535.5 Supposing it starts at r=1cm and goes clockwise, I have...

So here's a little background for the question: I have an arc that covers 3/4s of a circle (so it's not quite a full circumference) such that the radius from the center of the arc varies with respect to the angle (dR/d(theta)) (and it can be either positive or negative, but not constant). I am...

Homework Statement A bee goes out from its hive in a spiral path given in plane polar coordinates by r = bekt q = ct where b, k, and c are positive constants. Show that the angle between the velocity vector and the acceleration vector remains constant as the bee moves outward...

I am building a robot for the VEX worlds competition and, I was thinking of a spiral scissor lift. But my problem is I only have two mothers to use on this part of the robot. The robot has a square base, so the spiral has to be square. If you could give your theories of how it would work, that...

Hi All, I was just wondering why some galaxies look spiral (e.g. the milky way, andromeda, etc)? Is there a proven explanation for this? Also, it would be interesting to hear your thoughts/opinions.. Thanks! :)

Resource to supplement physics I being taught through "Spiral Physics" I just started Physics I this semester. Though our instructor has given a ton of downloadable PDF files to supplement our textbook, it is all information to read through and study. He has given us absolutely no practice...

Hi... first post here! Sorry if not in the right place. I am trying to decode the parameters for an xml file format and I would appreciate help in interpreting some parameters. I know the thing specified is a "transition curve" or clothoid curve, as the transition between a straight path and...

We know that there exists no such thing as a "rigid" substance in relativity. Now suppose we had a disc of uniform density the size of the Milky Way. When the "core" of the galaxy starts to rotate, the effects (tidal and gravitational) of this rotation propagate at the speed of light, which is...

Through a spiral pipe is circulating a fluid with high speed, this will lead to many effects and forces like inertia and gyroscopic effect. http://www.2live.ro/demo/Serpentina.bmp I do not know how to approach the problem in order to find the distribution of forces...

I am stuck on the following task; Create a 2D Parametric Plot showing a spiral path. The parametric equations for a logarithmic spiral are x=k^u Cosine(u), y=k^u Sine(u), where k is a constant, and u is the plot parameter. What does the value of k determine? I have been typing in the...

Homework Statement A proton moves in a spiral path when enters a magnetic field of 5 T. If the pitch is 5 cm, find the angle between v and B. Homework Equations F = B q v sin θ F = m v2 / r The Attempt at a Solution I am guessing that I need to break down the velocity into two...

Homework Statement See the attached link The Attempt at a Solution I considered each shaded part separately. For the one between ##2\pi ## and ##4\pi##, I set up: $$\int_{2\pi}^{4\pi} ((4\pi +\frac{\pi}{2})- (2\pi + \frac{\pi}{2}) d\theta$$ I used a similar method for the other portions...

Hi all! If space isn't a true vacuum, why doesn't our Earth lose its speed due to friction? I know that it's a near vacuum outside our atmosphere and the friction would be almost negligable. But in the course of a billion years, shouldn't it have an effect? Why aren't we slowing down...

Hi I'm working on a project where I need to develop a flight path to cover a circular area. I was thinking of having the plane follow an archenemies spiral. I found that the general equation in polar is r=a(theta)^1/n My question is if I have a specific distance I want each spiral to be from the...

The Milky Way is a Barred Spiral Galaxy 100,00 -120,000 Across. I was wondering if there is a website or list of what Stars of Constellations exist in what Spiral Arm. I there exists: Orion-Cygnus Arm Perseus Arm Scutum-Centaurus Arm Norma and Outer Arm Carina-Sagitarius Arm...

Hi guys ! Is there any Standards for thermal designing of spiral plate heat exchanger, like TEMA for shell and tube heat exchangers ?

I'm not usually into the "green" thing, but an unrelated interest brought me to the topic of spiral heat exchangers and I also received some encouragement. The idea is a small, low cost spiral heat exchanger for use in village sized water treatment, desalination, and for making showers...

Hope you enjoy the following, http://www.youtube.com/watch?v=_Ssc1GsqHds&feature=player_embedded From, http://planetsave.com/2012/10/20/galaxies-trend-towards-more-ordered-disk-like-forms-over-time-upending-old-assumptions/

A thin insulated wire forms a plane spiral of N = 100 tight turns, carrying a current I = 8 mA. The radii of inside and outside turns are equal to a = 50 mm and b = 100 mm. Find the magnetic induction at the centre of the spiral and the magnetic moment of the spiral with the given current...

At my fixed point of (1,1), I should have a stable spiral but I keep getting analytically that it is a saddle. $$ \begin{cases} \dot{x} = x(3 - 2x - y)\\ \dot{y} = y(-5 + 5x) \end{cases} $$ The fixed points are $(0,0)$, $\left(\frac{3}{2},0\right)$, and $\left(1,1\right)$. Also, the Jacobian...

Homework Statement It is common to see birds of prey rising upward on thermals. The paths they take may be spiral-like. You can model the spiral motion as uniform circular motion combined with a constant upward velocity. Assume a bird completes a circle of radius 6.00m every 5.00s and rises...

[a]Give a parametric equation for the line tangent to this curve at t = \frac{pi}{4}. \vec{r(t)} <e^tcost, e^tsint> Give the equation for this same tangent line in the form ax + by = c [b]My attempt \vec{r(\frac{pi}{4})} = <e^\frac{pi}{4}cos\frac{pi}{4}, e^\frac{pi}{4}sin\frac{pi}{4} =...

Hi, Is it possible to help to accelerate an object with an Archimede Spiral ? We can apply a force F perpendiculary to the spiral, like this if we want to turn the spiral in its center we don't need energy. If we want to accelerate an object near the spiral, we apply a force F to the spiral...

Homework Statement 27. Use the parametrization x = tcost, y = tsint of the Archimedean spiral to find the arc length of the first full turn of this spiral (corresponding to 0 <= t <= 2∏ ). Homework Equations The Attempt at a Solution I use onenote and a tablet, so my exact attempt in in the...

Is the Milky Way winding up like spaghetti on a fork, or spinning out like frosting in a blender?

There is observational evidence for preferred alignment of spiral galaxies with alignment to the so called axis of evil in the CMB (cosmic microwave backgound 2.75K) data. http://arxiv.org/ftp/arxiv/papers/0707/0707.3793.pdf http://arxiv.org/ftp/arxiv/papers/1104/1104.2815.pdf

Homework Statement a logarithmic spiral is given. The center lies on the x-axis. after a turn of 180 degrees counterclockwise I am 86.23m away from the starting point, after 360 degrees I'm 75.41m away from the start (radius, not along the spiral). Where am I after I walked exactly 3km along...

Homework Statement Find the curvature of the spiral of Archimedes r = 2θ Homework Equations ||v x a || / ||v||^3 The Attempt at a Solution I tried to convert the polar equation into parametric and got x = 2θsinθ y = 2θsinθ z = 0 I think took the derivative of x y and z...

Hello, I'm in desperate need of some help with a problem regarding spiral motion. If a particle moves along a spiral path by degrees θ in time t with intial angular velocity ωo, can the rotational kinematic equation (θ = ωot + (1/2)\alphat2) still be applied? I'm trying to solve for angular...

Major brainfart here. Consider the spiral motion of a particle such that the distance from the origin to the particle is r(t) = e^t with a constant angular velocity. Now since the particle rotating with a constant angular velocity, I would think that the net force on the particle...

I have a simple geometry question hopefully I'm posting this in the right forum. I want to draw a simple logarithmic spiral using only compass and ruler or any other simple mechanical means. The requirement is that each spiral must be halfway from the center to the next spiral. Is there a...

Hi guys, I've been playing around with structure generated patterns and have come across one which has caught my attention. I am only just starting to learn about number theory and so I am sure someone might be able to provide an explanation for this. Let me describe what I did then show you the...

Hi, I'm an engineer designing a spring system for a garage roller door. I need to know the number of turns of the door for all the size combinations. I've found this page which gives a good equation for finding the length if you know the number of turns, starting radius and gap between...

I was just thinking about a problem for fun where n layers of tape of thickness t are wound on a spool of inner radius r and one needs to find the the variation of angular speed of spool as a function of time such that tape is obtained at a constant time rate v. But , my question is ...

Homework Statement http://img534.imageshack.us/img534/6164/questionv.jpg Homework Equations ω = dθ/dt v = dS/dt The Attempt at a Solution I used the second expression for the tangential speed: v = \frac{dS}{dt} = r \frac{d \dot{\theta}}{d t} = (b-ct) \frac{d(kt)}{dt} \therefore \ v(t)...

Hi everyone, I need some help ASAP please! I have forgotten how to calculate the length of a spiral in a cone. I am really only interested in part of the cone from where the diameter is 8m to the base where it will be 10m in diameter. in this part of the cone there will be 5 rotations each...

Hi, I am looking for a formula that calculates self inductance and capacitance of rectangular spiral coil, i came across many formulas for helical coil and circular spiral coil but couldn't find one for rectangular coil, any help is highly appreciated. Thanks