Point Definition and 1000 Threads

I have been thinking about the classic example of two twins traveling at different speeds and the effect of time passage. One twin that goes off to travel near the speed of light while the other twin is left on earth. We theorize that the traveling twin will pass through less time and be...

Large power generators (for example 200 MW) are cooled by H2 in gas form. H2 temperature is +45 to +75 "C. So why hydrogen dew point is important in generator while the lowest hydrogen temperature is 45 "C? And in some Power Stations is monitored online... Thanks, a lot

So I've got the following problem: I have points A, B, and C which form a triangle in a 3D space (each point of the triangle has x,y, and z coordinates). I need to find out on which side of the triangle point D lies. I do not have access to the normal of the triangle. How am I supposed to...

Since I'm computer engineer and don't have much experiences with electromagnetism, I'd like to know if it is possible to make an electromagnetic signal (250khz - 500khz) and send it to a point (with an error of maximum 1cm) in a room. If yes which devices do I need to setup my experiment?

I draw this diagram: The formula for hydrostatic pressure is: ##P=\rho g h## so I just plug everything $$P=1000 \times 9.8 \times 0.1=980 Pa$$ Will the acceleration of the cart affect the hydrostatic pressure? Another thing that came to my mind was there would be extra force coming from...

I am very new to C programming so am struggling with this question and how exactly to begin it, when we are doing this are we to use something like sprintf? Thank you.

Summary: Definition: If M is a set and p is a point, then p is a limit point of M if every open interval containing p contains a point of M different from p. Prove: that if H and K are sets and p is a limit point of H ∪ K,then p is a limit point of H or p is a limit point of K In this proof I...

I have tried to use the intial velocity v=(2gH)^(1/2) and tried to use conservation of energy, using potential energy to find the maximum height but still can't arrive to the answer provided. Don't know what concepts are relevant here, apparently I can't use velocity neither cosine or sine. I...

I'd like to understand how gravity does not combine with quantum mechanics. At least there is no accepted theory of quantum gravity, so I assume it is not solved? I'm only starting to learn QFT and eventually GR. Maybe, someone can already outline where those theories fail to combine and comment...

I am reading a popular-science book Reality Is Not What It Seems by Carlo Rovelli, one of the founders of loop quantum gravity. He writes: and and So basically, space (spacetime) is just another quantum field like all the others, and the quanta of this field is the nod. Nods have volume...

What is your thought and experience about it? What the mainstream consensus about it by general populations and by experts?

I know the solution already, yet I don't understand why I'm able to solve laplace's equation when the volume has a point dipole within; I thought this required Poisson's eauation, which I have no experience in solving. Here is the relevant part of the solution

I have a question regarding the collision of two objects, specifically something heavy falling on something with a point. For example, if a 50lb ball of clay fell from 10 meters onto the point of a knife, would the knife's point have to withstand the entire force of the clay before the blade...

So I get the exercise and all and have just solved it. But .. I kind of very very intuitively determined ##\theta## to also be the angle for the circular sector. The problem here is that my geometry bag is very weak, I didn't have any geometry in HS, will fix that sooner or later but anyway...

Hi, A body with center of mass behaves as a point mass when a force is applied. So when ##F_{ext}=0## then does it also behave as a point mass with ##a_{com}=0##, at rest. If yes, How can we prove this? (And can somebody please answer my other question I posted a week ago...

I got E. 13q as the answer. That is what i did: The electric field due to +q at origin 0 should equal the electric fields of charges -3q and the new charge placed at 2x. So applying the equation above like this; k*(q) / (2^2) = -3q*k + (k*C)/ 4 solving for C the new charge added, gives 13q. I...

I tried to solve it for some time and then looked at the solution manual, which got me completely lost. Those are the first lines of the solution : I'm not so sure how equation 4.39: makes him conclude that the same relation holds for dipole moments. My second concern is that I'm not sure how...

Hi, I want to know how to calculate the effective weight if i have an object with the weight 'X' that is mounted from the side to a wall, and what happens with the weight if i increase the distance between the wall and the object. The reason i ask is as follows for the interested. I have a...

I just have to accept at this point I’m a C student. Because no matter how much I grind or study I still do bad. Last semester I did terrible on all my test despite only taking 3 courses. Told myself I would do better from no on. Cut to now in the spring semester, and the same stuff is happening...

I'm following 《A First Course In General Relativity》.On page 72,it says"If the surface is spacelike,the outward normal vector points outwards.If the surface is timelike,however,the outward normal vector points inwards"I wonder why and how?

I am looking for a good working fluid whose boiling point is in the range of 150-180 F for a waste heat recovery system. The fluid should be minimally flammable, preferably nontoxic, and low in environmental impact. Does anyone know of any working fluids that match this description?

I drew out a small diagram to illustrate my attempt. I interpreted 280 degrees from the vertical as 10 degrees from the horizontal. Using trig I solved for the h, which I get an obviously incorrect answer. The actual answer in the book is 2.3m,

I am trying to figure out how to do a deflection profile for a snow ski profile at 50 mm increaments along the ski. Since the ski has different widths and heights at each crossection, the EI changes at each location making it a lot of 2nd order derivatives if I am not mistaken. I am assuming...

Potential of a moving point charge is given as ##V (\mathbf r,t)= \frac{1}{4\pi\epsilon_0}\int \frac{\rho (\mathbf r',t_r) }{|\mathbf{ (r-r')}|}d\tau'## Griffiths says: " It is true that for a point source the denominator ## |\mathbf{(r-r')}|## comes outside the integral..."Why does it come...

Apparently, there are two solutions where the electric potential is zero which I don't understand, can I get some input on how this is possible? I have one thing in mind (which I just thought of and might solve it), the equipotentiality i.e. when I draw a circle for V = 0 around the negative...

I have tried solving this by splitting the load into two parallel coplaner loads as the Hint below the question suggests but while i was computing the values i realized that, i'll have 4 variables with only 3 equations. two forces and the two distances to forces from their respective axes. i've...

I’m wondering if there is a formula for calculating the coordinate points of a polygon given the following - Center point is known - area is known - Point A is known - Points B, C, and D are UNKNOWN I am NOT a math pro - this is for a puzzle I’m trying to solve and I can’t remember if this...

Hello, I need help with this bjt transistor and finding the Q point. The problem I have is that I don't know how to do the thevenin theorem on this one. If someone could help me and show me how its done that would be great. Thank you! The transistor looks like this on the picture: This is my...

So I'm looking for some advice on a problem that I am trying to solve for a project. I'm an engineer but my background in vector mathematics is very minimal so I'm looking for some assistance. Lets assume we have a permanent magnet. We know the characteristics of this magnet, such as it's...

How do the energy and generalized momenta change under the following coordinate transformation $$q= f(Q,t)$$The generalized momenta: $$P = \partial L / \partial \dot Q = \partial L / \partial \dot q\times \partial \dot q / \partial \dot Q = p \partial \dot q / \partial \dot Q = p \partial q /...

I am looking for a formula. From a horizontal plane of 100 meters; If angle on the left is 8 degrees and the angle on the right is 21 degrees at what distance from the centre of the horizontal plane will these two angles converge?

1. One of the few negative effects of quitting smoking is weight gain. The data below shows the weight gain (in pounds) of 18 respondents 12 months after they quit. If the mean gain follows a normal distribution with a standard deviation of 9 pounds, estimate the mean weight gain of the 18...

Could someone help me?

If I have a point charge q right outside of a gaussian surface, it makes sense that the flux is zero inside the surface because the electric field going in equals the electric field going out. However, how would the electric field be zero inside? Wouldn't it just take on the electric field of...

Find the question here; My interest is on question ##3(c)## only. My approach, Let the co ordinates of ##C##= ##(x,y)## then considering points ##B## and ##C##. We shall have the gradient given by; ##\dfrac {y-4}{x-1}##=##-2## also from straight line equation, considering points ##A## and...

At point ##P(0,0'03,0'04)## the field caused by the sphere is added to the field caused by the plane. First, ##E_\sigma## $$E_\sigma=\dfrac{\sigma}{2\varepsilon_0}=\dfrac{0,2\cdot 10^{-6}}{2\varepsilon_0}=11299,44\, \textrm{V}/\textrm{m}$$ Then, ##E_0##: Because ##r<R##...

Point B is elastic limit and point C is yield point. From this link: https://en.m.wikipedia.org/wiki/Yield_(engineering)#Definition The definition given is: Both seems to refer to same definition, it is the point where the elastic deformation ends and plastic deformation begins. But from...

Disclaimer: This is not a repost. The problem wants me to calculate the force of a p.c. , that is isolated by itself (this p.c. is the only charge this problem starts with in this problem) inside a capacitor, a distance h/4 from the bottom plate. This is what I have though of so far but I...

λ1 = 3 microC/m λ2= -4 microC/m __________ . __________ l----L1---l-a1-l-a2-l-----L2---l (Not to scale) L1 = length of rod 1 (1m) a1 = length of end of rod 1 to point (0.7m) L2 = length of rod 2 (1m) a2 = length of end of rod 2 to point (0.3m) k = e field constant...

The first image is the question and the second is the answer. My thinking is let's say North is positive, and South is negative. Fixed point O is the starting point. Then the question becomes +(2a-b)-(3a+2b). The answer should be -a-3b. I cannot fathom why the book gives the answer as a+b. Any...

For (a) this problem, the only thing I can see changing is the distribution of the negative charge on the inner wall of the cavity. When the point charge is in the center of the cavity, you could say the induced charged is spread symmetrically on the inner cavity wall in order to oppose the...

I believe I have all parameters set up correctly to evaluate part A of this problem but I am unsure of the bounds. I can't integrate from 0 to R because that part of this sheet has a hole there. I need to integrate from R to the other end of the sheet. Im not sure how I would figure out the...

I've calculated the intensity for every point charge which are EA = 6.741 x 10¹³ NC¯¹ EB = 4.494 x 10¹¹ NC¯¹ EC = 6.741 x 10¹³ NC¯¹ and I am pretty sure about this far but I am struggling to calculate the X-axis intensity and Y-axis intensity to find the entire approximate intensity with the...

Hello all, I am hoping to get some feedback on the manner in which I performed computations towards solving the following problem. There are a couple specific points which I am not confident of: 1. Did I properly account for the manifold structure in my computation of the nonzero components...

The removed mass is ##\frac{1}{8}M## My idea is to find ##g## from large sphere then minus it with ##g## from small sphere (because of the removed mass): ##g## at A = $$\frac{GM}{R^3}\left(\frac{1}{2}R\right)-\frac{G\left(\frac{1}{8}M\right)}{R^2}$$ Is this correct? Thanks

Hi. I have this idea that might be useful for celestial navigation. If you were on a random place on the Earth, and you had a way of measuring the altitude of the sun above the horizon, at a precise moment, could you then predict the complete path, such that you could determine the altitude at...

So we are finding the L2 Lagrange point, specifically the distance from the earth, or d in this instance. I have used the equation above and I have come out with 1.5 * 10^9 meters as d, or L2's distance from the earth. Can anyone verify this, is the equation correct and is my final distance...

I tried solving the part (a), and got I =1.82 A for the current value using Kirchoff's law. Next, I want to use Ohm's law to calculate the voltage at point a. Va = IR In this equation, will resistance R correspond to 4.4Ω or 8.8Ω? How do you determine which resistance to use when solving this...

I don't get what is meant with the last part: that takes any one given point to any other given point. Thanks in advance