Spiral Definition and 182 Threads

I was trying to figure out how much landscape fabric I have left on a roll, given a known thickness ##T## of the fabric and the radius ##r## of that roll. I obviously don't want to do an integral to calculate it while I'm working, but was looking for some approximation that can be readily...

I have a disk traveling on the inner blue track (let's say the blue part is the center of the disk). I want to push the disk outside (as the disk is traveling in a circle) to the outer track. The black part is the wall separating the tracks To that end, I've made some calculations, but I have...

Hot air rises due to the candle below. But how does that create a horizontal force, which is needed to produce the rotational torque?

Could someone explain the geometry of this graph? Why does the radial distance vary non-uniformly? To-wit: Distance from origin to Nov 2020 is much larger than Nov 2020 to Nov 2021 Why are there two areas - one above and one below - the centre line...

Had to Google Flocculent, adjective having or resembling tufts of wool. "the first snows of winter lay thick and flocculent" having a loosely clumped texture. "a brown flocculent precipitate"...

Would need advise on which is the maximum allowed compression to apply to a gasket according to the thickness of the gasket. If this information is available from the manufacturers, would like to know. Also, if once used, the gasket can be reinstalled and which is the experience about that.

I want to focus this question on understanding the force ##F(r)## I get (thus, I want to focus on c) ). However, below the dashed line, I included steps on how I derived ##F(r)##. We are going to work in polar coordinates. Knowing that the acceleration is: $$a = \Big( \ddot r - r \dot...

I believe I solved this. Is this solution true? Can please anyone just check?

Want to let the steel ball move upwards at a uniform speed, how is the torque of the spiral tube calculated? The parameters can be assumed by themselves. **The spiral tube is fixed on the central shaft, the central shaft is mounted in the ball bearing, and the thrust F acts perpendicularly on...

Summary: is it possible to heat a coiled spring If I had a spirally coiled spring like inserted pic, spiral coiled spring approx. 300mm dia and spring section +-12mm dia with +-1mm gauge wire, with a total length of spring approx. 4mtr-6mtr , is it possible to heat this with induction heating...

Other than compact binaries, are there conditions where 2-body inspirals circularize? 3-body? Thx

There’s an obvious resemblance between a spiral galaxy and a cyclone. They have the same spiral shape. I was wondering if the equations describing both motion are the same. I googled vortex motion but equations and concepts looked very specialized and complex for me to understand easily. Thanks.

Recently I have studied that from the rotation curve of spiral galaxies, the nearly constt. behaviour of velocity of the stars situated far away from the central core suggests mass(r) ~ r ,rather than 1/√r as expected. Are there any other theory which proves the existence of dark energy ??

Could anyone please explain how can I know mathematically whether the logarithmic spiral curve spirals inward or outward? In which sense does the outward spiral spirals? Thank you very much for your help

Homework Statement As you'll know, the driving force for a circular movement is a centripetal force. But wat is the dynamics for a spiral movement, i.e. an increasing circular movement? And how can I produce it, let's say for a little spherical object, in real life? The Attempt at a Solution I...

Homework Statement Consider a spiral of 20 turns with inner radius R and outer radius 2R. If the current is i, find magnetic field at the center of spiral Homework Equations From Biot-Savart law-dB=mu(idl)/4pi*x^2 The Attempt at a Solution Integration seems like a good option. x is...

Hi I have found a video which is composed of 2 videos. In the first one you can see that a spiral branch is put into a stream and starts to move by itself in a snake like motion. In the second video similar spiral piece of wood is floating in a container and then water is poured into it and it...

Homework Statement https://projecteuler.net/problem=58 Homework EquationsThe Attempt at a Solution def prime(N): if N == 1: return False y = int(N**0.5) for i in range(2,y+1): if N%i == 0: return False return True def finder(N): L = len(N)...

Spiral galaxies of course rotate around one axis perpendicular to the plane, but has anyone measured if any spiral galaxies are also rotating about an axis through the plane or about any other axis?

<Moderator's note: Image added because otherwise the thread might once become unreadable.> I have reason to believe this could have applications in physics, but right now it's just a mathematical result I came across recently. Either way, I think it is very interesting and fun to look at. This...

Does the 11 year magnetic pole reversal affect the sun's magnetic field configuration as manifested by the Parker Spiral? (BoB 2nd Ed., Page 380) How rapidly does the field this spiral describes decline? Is it an inverse square in attenuation? How does this affect Earth? Thanks.

Hi, I was looking for a quantum physics phenomenon including in quantum field theory where the solutions of a related phase-plane system (i.e. the harmonic oscillator) have a spiral sink in the phase portrait? The harmonic oscillator has saddle points in the phase-portrait, given its eigenvalue...

How spiral torsion spring (used in mechanical watches to store energy) works? physics behind it ? ... I googled it but haven't got a clue. Where should I look for proper and detailed info.

Please help me... Tell me how to find real torque for rotating spiral of dough mixer. We need to mix 25kg dough with adding water and Ingradients. Spiral made by ss rod of 25mm dia. Spiral dia is 250mm. Rotating speed is 250rpm(max). When start the machine rotate both spiral and bowl. Dough...

Starting from the origin, go one unit east, then the same distance north, then (1/2) of the previous distance west, then (1/3) of the previous distance south, then (1/4) of the previous distance east, and so on. What point does this 'spiral' converge to? I have attempted to sketch this out but...

Assume an object accelerating at a certain value dV/dt. If this object was traveling in a circular motion the centripetal force would increase as the object moves faster. To maintain centripetal acceleration constant while the object is accelerating (in its forward motion dV/dt) I think it...

Homework Statement We've got an object/person in the center of a cicrcle that spins around with an angular velocity ω. That same object is moving at a constant speed k with the direction of the radius, that is from the center to the outside of the sphere. That object describes then a spiral...

I have a concern about a method for drawing an Archimedean spiral. If a spiral is drawn by rotating a string around a rod, it would only be an approximation of an Archimedean spiral. Starting from the edge of the circle, each time the string goes around once, the change in distance from the...

hey, I just want to know, if I am to send a velocity commands to generate a spiral trajectory, What would be these velocities (angular and linear)?? Thanks in advance

Hi, i have this problem..., giving two circle (example radius 1 = 500 units, radius 2 = 200 units, distance between centers = 275.73 units) find Euler Spiral (aka Cornu spiral, aka Clothoid https://en.wikipedia.org/wiki/Euler_spiral) tangent giving circle (unknown tangent points). For this...

Draw a single light ray through a spiral phase plate, anywhere but the middle of the plate, with the incoming ray being parallel to the axis of the spiral phase plate. On passing through the plate the ray is no longer parallel to the axis of the phase plate? Does the change in direction account...

Hello everybody, I have a planar spiral coil with wire. I want to move a magnet in vertical direction with the magnetic force generated by coil. I want to know how much impulsion to magnet will be occurred on vertical direction. I have been searching for the answer but I am a little bit...

Charles Link submitted a new PF Insights post Frenet Equations in 2-d Which Result in the Cornu Spiral Continue reading the Original PF Insights Post.

Why do the arms of spiral galaxies usually bifurcate? Is the visible matter in them moving in or out from the center?

I have question that has been troubling me and I was hoping someone may be able to help me. I've always thought the Hubble classification of galaxies was a bit subjective. I was recently looking at some images online of galaxies and I was wondering how you might objectively observe and compare...

Hi there- I'm a graphic artist and work on a lot of "Spiral" cans. A good examples would be a Pillsbury Crescent roll can (after you whack it on the counter and unroll it). Or, a frozen Concentrate orange juice can unrolled. Anyway, I've created formulas in Excel to setup the page size that the...

Homework Statement Evaluate the length of the spiral with parametric equation ψ(t) =< 2 cost, 2 sin t, π/t >, with t ∈ [0, 2π]. Homework Equations Line integral ∫C f(x,y) dS The Attempt at a Solution f(x,y) = z = π/t ∫C π/t dS [0, 2π] are the lower and upper bounds of integration dS=...

Hello everyone, I did an experiment titled 'mass on a spiral spring' in order to find the value for the acceleration due to gravity. The experiment consists of two parts. In the first part of this experiment, I just measured the oscillation period of a spring as a suspended mass and plotted...

Homework Statement What type of spiral has constant angular velocity and constant magnitude of velocity? Is there a description of the mathematics that describe the spiral? Homework Equations To be determined. The Attempt at a Solution The closest type I can find is the Archimedean spiral...

Homework Statement A thin insulated wire forms a plane spiral of N turns carrying a current ##i##. The inner radius is ##b## an outer radius is ##a##. Find magnetic field at centre of spiral Homework Equations $$B=\frac{n\mu_0i}{2R}$$ The Attempt at a Solution For an area of ##\pi(b^2-a^2)##...

Hi. I want use high temperature spiral sleeves which should withstand around 300 deg C and I want wrap these sleeves around power cables which are passed in enclosure having thermal block and we will heat this block up to 400 deg C Please suggest me how to overcome and suggest best suitable...

How did we know that our galaxy is spiral?!

Hi! I am new to ANSYS and I am trying to understand a simulation done by some one else. I have a disk with a spiral in it, and it looks like there is a remote force being applied at the centre of the disk, but spread over the entire face. I don't understand how this force is being spread...

Hey there! Usually we learned to calculate (in this case, I learned mostly in square/rectangular shapes), but I would like to ask how to we calculate spiral loadings? How would the load be transferred when the structure is in spiral shapes? Thanks! Here's an example of the structure.

Trying to figure out direction of forces of an object traveling on an Euler spiral path. As an example if you had an astronaut with a jetpack and he wanted to change his direction 90 degrees he could aim his thrusters outward from the center of a circle and he would turn at a constant rate with...

I was reading a fiction book and they mentioned a fascinating concept described as "spiral time" - are there any credible scientific hypothesis concerning such as thing - no matter how generally outlined? The concept, obviously is that time is neither a unidirectional timeline nor a circular one...

Hi, I hope this is the right section. I'm trying to figure out a rough estimate of the pressure drop in a spiral heat exchanger. The fluids both being water. My guess it it would be in terms of the surface area of the inside of the heat exchanger, and the flow rate, but I can't seem to nail...

I believe what I am attempting to do is not possible but here goes. I want to design a fixed overall length coil which I can manually adjust the pitch on. Optimally one would be able to grab the coil and by twisting it in place would be able to change it's pitch by changing its diameter but not...

For any 2 pairs of points (xe,ye) & (xs,ys), I can fit various equiangular spiral through those 2 points based on the equation r = ke^(aθ). A typical one is illustrated below: Then, I can vary the origin of the spiral -> i.e. (xc,yc) to generate another equiangular spiral which passes through...

Hi, i am in second year of university and doing optics I have a questions in one ofmy assignment : Fresnel diffraction is observed behind a wire 0.37 mm thick, which is placed 2 m from the light source and 3 m from the observation screen. If the light of wavelength 630 nm is used, find, using...