Lines Definition and 1000 Threads

We've all seen these photos of the crosswalk (or other street lines) on the asphalt distorted when the driven tires of cars push back as they roll forward. (At least I'd like to think we've all seen them.) I used to have one I took myself a long time ago. But, for the life of me, I can't seem to...

How can we add lines, text etc onto a bitmap image (for example one created via Rasterize[] ), using Mathematica commands? At the moment my use case is that I want to ListPlot[] a graph that has about a million plus line segments. My free WolframCloud account runs into memory limits when...

Force lines method is used in Solid Mechanics for visualization of internal forces in a deformed body. A force line represents graphically the internal force acting within a body across imaginary internal surfaces. The force lines show the maximal internal forces and their directions. But...

Hi, I was watching the following video. I need your help to clarify few important points. Thanks a lot in advance! Question 1: I'm not able to understand picture #1 below. I think that the frequency increases vertically downward but what about the horizontal scale? Compared to picture #1...

I tried by one way, seems ok and makes sense, but i am not sure if it is valid yet. $$P_{a} = c_{a}V_{a}^{(-\gamma_{a})}$$ $$P_{b} = c_{b}V_{b}^{(-\gamma_{b})}$$ $$(Pa,va = Pb,vb)$$ $$\frac{c_{a}}{c_{b}} =\frac{[V_{b}^{-\gamma_{b}}]}{[V_{a}^{-\gamma_{a}}]} = V^{-\gamma_{b}+\gamma{a}}$$ Now this...

In the picture below, the direction of the magnetic field lines can be determined by using the right-hand rule with the thumb pointing in the direction of the current. If we use the right hand rule in the picture below, thinking of the yellow arrow as the current, we would not get the correct...

Hello all, I have produced a contour plot of a given function f. To this, I have added the vector field (arrows) for the gradient of f calculated analytically. I have then also added the vector field numerically by using the np.gradient function in python. In both cases, the vector field...

Hello, I am currently in my college holidays and I have decided to do some maths to improve. My weakness is graphing and I am hoping to get some help or the solution on this question. Question: Let P(k,k^2) be a point on the parabola y=x^2 with k>0. Let O denote the origin. Let A(0, a)denote...

In ##\mathbb{R}^2##, there are two lines passing through the origin that are perpendicular to each other. The orientation of one of the lines with respect to ##x##-axis is ##\psi \in [0, \pi]##, where ##\psi## is uniformly distributed in ##[0, \pi]##. Also, there are two vectors in...

figure 1: → I don't understand how to approach this problem. Basically it asks for the distance r.I think I should use Gauss's law, but I've been thinking about the shape of the gaussian surface and I'm not sure about how it should look or where I should place it. Any help would be useful...

In the universe do straight lines exist? I know over long distances like interstellar and even shorter distances like between the Earth and around the gravity of the moon lines tend to curve, but do straight lines exist anywhere? Or just a desire for them to exist in nature if not for gravity...

Hello All, See picture below: There exist an infinite plane with infinite number of dots. For sake of argument, let's assume they are 1 inch away from each other. However, below(on your far left) you can see 3 lines already made. The last line is the yellow one. What you see on the left, are...

I've been able to find the tangent line with most equations, but I don't have any idea how to do it with a range of values instead of being given a singular value.

Hi, I am interested in finding the equation for electric field equipotential lines. Ideally, it would be nice to have one equation that worked to find it for different geometries. Unfortunately, I don't think that exists. Assuming it does not exist, I think I would probably have to either solve...

I really don't want to get into politics, I am sick and tired of smelling and breathing the smoke from the forest fire in N Calif even I am living in the silicon valley. Trump said because Calif refuse to clear fire break lines, clear the debriefs, then once the fire started, there is no break...

I think that we can say that PPR = α*PRPS where PR and PS are the points where occurs the intersection on the line R and S. Obs: line r and s are found by knowing that the straight line intersection of two planes are n1 X n2 [cross product] Lr = (0,1,-2) + y(-1,1,1) Ls = (0,1,-1) + u(1,2,1)...

I was initially curious by the fact that streamlines around a circle appear the same as the lines of stress around a hole: I understand that streamlines are the contour lines of the stream function ##\psi## which satisfies the Laplace equation. I was wondering there is a related function for...

I have an ordinary switchable magnet for holding tools to a lathe. It's like a magnetic force gearbox, but I can't quite understand the force multiplication. When placed on a steel surface the switch force is approximately ~5N on both finger and thumb at 1.5cm radius acting over a 3cm arc...

Hope someone can help!

Many years ago I was responsible for maintaining the integrity of a buried fiber optic cable that utilized a railroad right-of-way. Kinda like watching submarine races ! Along much of this routing, transmission towers / power lines would be adjacent to the railroad. Talking with railroad...

Thought of doing this one years ago! Basically, I want to 'see' the magnetic force lines that surround a conductor when energized (with an alternating current). I appreciate that what I will see (or at least I am hoping to see) is the pattern formed by the iron dust in response the the field...

not quite sure if this is right.. can someone confirm?

How are different elements spectral lines naturally 'scrambled' and then differentiated by observation, into each and every element contained in a 'single' light beam emanating from a light source? Is the term 'single' correct in this context and if not can you explain why?

Does anyone know theory about how the perturbation lines are for 1s hydrogen electron? By perturbation I mean the perturbation that is caused by moving an electron so that the E-field lines it emits becomes dragged. by perturbation I mean for example dragging a charge as described below Above...

Do they mean something like this?

How can traveling wave exist on transmission line if wires are perfect conductors (how voltages can be different at different positions on one perfect conductor)? I mean electric fiels should be zero on equipotential source. I know if length is too long compared to wavelength, we get phase...

$\tiny{3.2.15}$ Find the number c that satisfies the conclusion of the Mean Value Theorem on the given interval. Graph the function the secant line through the endpoints, and the tangent line at $(c,f(c))$. $f(x)=\sqrt{x} \quad [0,4]$ Are the secant line and the tangent line parallel...

Hey! :o I am looking at the following: 1. We have the function $f(x,y)=y-x^2-1$. Write the appropriate commands in Geogebra that draw a contour line with $f(x,y)=\frac{3709}{2000}$. Could you give me a hint what command we have to use here? Do we just plot $y-x^2-1=\frac{1374}{2000}$ ...

I read these lines from the book Ideas and Opinions by Albert Einstein- "Gradually the conviction gained recognition that all knowledge about things is exclusively a working-over of the raw material furnished by the senses." what I interpret from is that knowledge is obtained by observing...

I was asked in a test this question: Electron in hydrogen falls from level 4 , how many lines we will see on the ejection spectrum? I hope I translated it well. I see a lot of question about those lines but can’t find information about it. Can anyone explain it to me?

I'm trying to understand the relationship between the "number" of field lines passing through a region and the magnetic force in this region.I understand that the drawings are of course conceptual: we cannot draw "all" the field lines (although can be visualized with iron fillings).Also the...

Hello. My current understanding (please correct, if wrong) is that the expansion of the universe is observed to be accelerating, rather than coasting or slowing down. The tentative cause of this acceleration has been given the placeholder name of 'Dark Energy'. One line of evidence for this...

Hey, not sure how to translate this from my native language, I hope you understand what I mean. Write down for the line y = 2x + 3 perpendicular and parallel lines passing through the point (1; 1) equations.

Why do we see more absorption lines in stellar spectra than emission lines?

The equation we used in this lab was Δλ = (λ^2 / 2Δd) where Δλ is the separation of the sodium D doublet lines and is the value we're trying to calculate, λ^2 is the wavelength of sodium light given in the lab manual (589 nm) and Δd is the distance one of the mirror moves to go from one faint...

9. When I do this problem I know my slope is -3 because f'(2)=-3. I then went and substituted and got y+5=-3(x-2) which simplified to y=-3x+1 10. I get lost here because the tangent slope would be 0, which would give me the equation y=-2. The normal means perpendicular and the perpendicular...

While determining the condition for the pair of straight line equation ##ax^2+2hxy+by^2+2gx+2fy+c=0## or ##ax2+2(hy+g)x+(by^2+2fy+c)=0 ## (quadratic in x) ##x = \frac{-2(hy+g)}{2a} ± \frac{√((hy+g)^2-a(by^2+2fy+c))}{2a}## The terms inside square root need to be a perfect square and it is...

Why are ground clearances so large for 765 kV towers? I did a little research on this and even if the switching surge factor is 3 and you have a factor of safety of 1.5, in air (3 kV/mm), it corresponds to 1.62 m of maximum arc length, which doesn't explain why towers are so large. According...

I own a HP Probook 450 G6, with Windows 10 Professional. The laptop was working properly till today morning. Now, when I started it this evening, I started getting spurious lines from MS edge. Chrome is displaying complete black screens. PF from MS Edge Gmail from Chrome PF from Chrome...

Homework Statement: This is not for homework but I have an AP physics exam on field lines and am confused about the proportionality between the charges of objects and the number of field lines. Homework Equations: E=(k*q)/r^2 I am struggling with the number of field lines to put based on the...

Hey, this is a problem given to me by my prof for an assignment, and the TAs at my tutorials haven't been much help. Was wondering where to go with this question. Also, I'm a uni freshman who isn't used to the whole concept of proofs, and a lot of what my profs say seem to be a slew of...

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If I have two line segments, how can I find the smallest distance between them? Any one point on each of the segments can be chosen for comparison. (to go a step further, a circle's outer edge and a line segment) Thanks in advance.

In the USA, the usual solution to keeping water lines from freezing is to bury them. In cold climates this implies digging deep trenches. (On another forum, a person from Minnesota said water lines are typically buried 7 ft deep.) In the days before modern excavating equipment, were...

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Let's for example consider the Z boson. It can't directly be detected; so is it ever really correct to draw it as an external line on a Feynman diagram? I've seen processes involving it before be written as something -> Z + something, then Z -> ... but since unstable particles aren't really on...