parts Definition and 838 Threads

I separated the circuit into parts- upper and lower For the upper loop I wrote: -14-2I1-3.4I3-I2 = 0 For the lower loop I wrote 16-2.9I2+3.4I3-5.4I2 = 0 I solved for I1 and I2 separately and plugged it into the junction rule and solved for I3. I may have got it wrong because of the...

I keep coming across this descriptor, "two (or three) independent, non-interacting parts," in many books on QM (for example, Penrose's Shadows of the Mind). It is usually followed by a mathematical description (for example, state vector |A>|B>). I can wrap my mind around the quantum paradox of...

Using integration by parts: $$I_n=\left. x(1+x^2)^{-n} \right|_0^1+\int_0^{1} 2nx^2(1+x^2)^{-(n+1)}dx$$ $$I_n=2^{-n} + 2n \int_0^{1} x^2(1+x^2)^{-(n+1)}dx$$ Then how to continue? Thanks

I was asked by an interviewer the number of degrees of freedom (in both translation and rotational senses) this part has with respect to each axis. Indeed I can share what I think of here, but I want to start it fresh and correct. If you were the interviewee, what would have been your answer and...

I work for an aerospace supplier across different departments. I was recently shown how the production workers straighten aluminum parts after a glycol heat solutionizing process. The aluminum parts undergo a heat treatment for a few hours and are quenched in glycol. I can't get too in-depth...

Recently, I've seen several discussion threads here about splitting electric fields. I want to express my opinion. Of course, this is just a calculation method, not a basic physical concept, but it is also useful in some cases, at least not wrong. The following is an example of the out of a...

Suppose someone throws coins and once they fall on heads or tails, she saws them along the middle on two parts: one pointing towards the ground and the other pointing from the ground. Then she sends those two parts into opposite directions so after some time they reach two distant planets, one...

Perhaps that's a very dumb question, but I'm having a hard time to understand why it's possible to omit parts of the equations in solving various problems involving oscillations. Here, for example, the complete equation for acceleration is not used (the part with cosine doesn't appear) and here...

I have read people with schizophrenia and DID may experience thinking that the world has become less real. Are certain parts of the brain acting up that could be making reality seem less real?

Hello I am just curious about something. In the image above, the spike shaped thing at #1, and the long thing at #2, what are those and what are their purposes? Since I don't know what they're called I can't google them lol. My current guess is that #2 is a mount for missiles, and #1 has...

How can i move from this expression: $$\frac{4}{\pi^{4}} \int dk \frac{1}{k^2} \frac{1}{(1+i(k-k_{f}))^3} \frac{1}{(1+i(k-k_{i}))^3}$$ to this one: $$\frac{4}{\pi^{4}} \int dk \frac{1}{k^2} \frac{1}{(1+|k-k_{i}|^2)^2} \frac{1}{(1+|k-k_{f}|^2)^2}$$ using Feynman parametrization (Integration by...

In Keisler Elementary Calculus page 39, example 4 it shows how to compute the standard parts of the following expression: Example 4: If ##\epsilon## is infinitesimal but non zero, find the standard part of ##b=\frac {\epsilon} {5-\sqrt{25+ε}}## Before calculating the standard parts the...

If ##\psi(x, t)=\left(\frac{1}{2 \pi \alpha^{2}}\right)^{1 / 4} \frac{1}{\sqrt{\gamma}} e^{i p_{0}\left(x-p_{0} t / 2 m\right) / \hbar} e^{-\left(x-p_{0} t / m\right)^{2} / 4 \alpha^{2} \gamma}##where * ##\gamma=1+\frac{i t} {\tau}##( a complex number) * ##\tau=\frac{m h}{2...

Hi, I am trying to build a tortilla pressing device. If possible could anyone let me know what are the parts i need to get and also the size/power of the pneumatic cylinder should be. Thank you.

Hi. Would it be true to say, that a ferrite rod antenna, operating at fairly low frequencies (say 1Mhz) for all intents and purposes, only responds (in terms of voltage output) to the magnetic field part of a "radio wave"? Thanks.

How much of Earth atmosphere consists of condensed phases? What is the breakdown of these condensed phases between those that condense in atmosphere (water) and those that do not (rock)? The total amount of water in Earth atmosphere is quoted as a 25 mm layer on average - total of about 13 000...

Hi, I have to find the real and imaginary parts and then using Cauchy Riemann calculate ##\frac{df}{dz}## First, ##\frac{df}{dz} = \frac{1}{(1+z)^2}## Then, ##f(z)= \frac{1}{1+z} = \frac{1}{1+ x +iy} => \frac{1+x}{(1+x)^2 +y^2} - \frac{-iy}{(1+x^2) + y^2}## thus, ##\frac{df}{dz} =...

I simply plugged \phi = \phi_0 (\eta) + \delta \phi (\eta, \vec x) into the given action to get \begin{align} S &= \int d^4 x \left[ \frac{a^2}{2}\left(\dot \phi^2 -(\nabla \phi)^2\right)-a^4V(\phi) \right] \nonumber \\ &= \int d^4 x \left[ \frac{a^2}{2}\left(\dot \phi_0^2 + (\delta...

In the days when scores were written by hand, how were parts for drums written? It's clear that ordinary notation is sufficient to indicate the duration of dumb beats - although writing each beat for a drum would be tedious. Was there some system of abbreviation? Did composers attempt to...

Hi guys, I've attempted to integrate this function by parts, which seemed to be the most appropriate method... but apparently, I'm getting something wrong since the result doesn't match the right one. Everything looks good to me, but there must be something silly missing :) My attempt:

As we all know, integration by parts can be defined as follows: $$\int u dv = uv - \int v du$$ And the usual strategy for solving problems of these types is to intelligently define ##u## and ##dv## such that the RHS integral can easily be evaluated. However, something that is never addressed is...

I know how to work through this problem but I have a question on the initial separation of the wave function. Assuming ##\psi(\rho, \phi) = R(\rho)\Phi(\phi)## then for the azimuthal part of the wavefunction we have ##\Phi(\phi)=B\left(\frac \rho\Delta cos\phi+sin\phi\right)##, but this function...

So I am confused about a proof in which the formula for expected value of velocity, ##\frac{d\langle x \rangle}{dt} ##, is derived. Firstly, because the expected value of the position of wave function is $$\langle x \rangle =\int_{-\infty}^{+\infty} x|\Psi(x,t)|^2 dx$$Therefore...

I'm reading Coleman's "Aspects of symmetry" chap 7. On the topic of the SU(2) winding number on ##S^3##on page 288, three parameters on ##S^3## are defined ##\theta_1,\theta_2,\theta_3##. Afterwards, it defines the winding number and to show it's invariant under continuous deformation of gauge...

Hi folks, Any idea about what is it? I am required to find parts like these items which are made of stainless steel 304 and used on the post-treatment of diesel engine gas.

For parts (d) and (e) I can't figure out the required steps to get the height due to the fact that I don't have the acceleration. I may have done a miscalculation for the former questions as well. I also feel (e) requires the value of a. Hope someone can help me out. Been going at this question...

Let's present two examples $$-\frac 1 2 \int d^3x'\big (-i \phi(x', t)\nabla^2\delta^3(x-x') \big )$$ Explicit evaluation of this integral yields $$-\frac 1 2 \int d^3x'\big (-i \phi( \vec x', t)\nabla'^2\delta^3(\vec x-\vec x') \big ) =\frac{i}{2}\phi(\vec x', t) \nabla' \delta^3(\vec...

i would appreciate alternative method...

There is a paper here: https://www.mdpi.com/1099-4300/19/5/188 And a lengthy article here: https://www.quantamagazine.org/a-theory-of-reality-as-more-than-the-sum-of-its-parts-20170601/ The general argument concerns causal emergence and whether all causal agency arises directly from the micro...

Looking to get parts made and heard about Xometry. Has anyone here used them for CNC or 3D Printing?

Suppose you have a complex-valued function of a complex variable (namely, ##z=x+iy, \, \, x,y\in \mathbb{R}##) defined as the assumed convergent infinite product $$F(z)=\prod_{k=1}^{\infty}f_{k}(z)$$ Further suppose ##F(x+iy)=u(x,y)+i v(x,y)##, where u and v are real-valued functions. How to...

Hi, I'm currently doing a shrinkage study upon this plastic part. I hv been observing how much can the part able to shrink over the time after molding, and now hv been on the 5th month observation. However, on the 5th month, the part starting to expand, compared with the data from the 4th...

can integrate 1/(x*lnx) by parts??

On the basis of what brain is classified,like we say on the basis of function the neurons are of 3 types.

In the circuit below, the output is 23 W across the resistor with the resistance 6 Ohm. Calculate the amount of current in all parts of the circuit as well as the polarity and EMF ε of the unknown battery. Circuit: My attempt: I get 6 unknowns with 5 equations. I don't know how to find the...

Hello, I am building a battery pack to charge my laptop cooling pad and I am looking at batteries for it. I decided on LiPo because it is thin and thus should fit better on the cooling pad. I do not need help with the design since I am planning on using pre-made parts (although if you are...

Hello, I am interested in knowing if a single-step wastewater clarifier/reclaimer can be made for used Parts Washer effluent. References can be found here :- 1. https://www.stingraypartswasher.com/stingray-mart-eq-1-wastewater-processing-system.html 2...

So, true story: I made a large circular tortilla. Ate half of it. Then decided to put the rest into the fridge on a smaller plate.I raised the knife to cut the remaining semi-circle in two, and then went : "Hmmmmmmmm...". Anyway, it's in the fridge now with an approximate solution, but I'm...

Hi, I'm only trying to understand the basic concept. Did the big bang give rise to both observable and non-observable universe? I have been through quite a few source and it seems like that the big bang was the cause of only observable universe and not of unobservable universe. Below I have...

The thing is that my professor said that if the velocity of ##A## is ##400 cm/s##, the velocity of ##B## is ##200 cm/s## because "##B## is connected to two parts of the rope and ##A## is conected just to one part", and he also said that that ##200 cm/s## is the velocity of ##B## with respect to...

In Newtonian gravity, non-rest mass contributions to gravitational effects are ignored and for many purposes (e.g. low precision solar system astronomy, N-body approximations of galaxy or galaxy cluster dynamics), the other contributions that enter Einstein's field equations through the...

I have known and used this theorem for a long time solving problems ("Calculate the CM of the some given shape"). I took the theorem to be "obvious" and didn't know it could be proved (and that indeed it was a theorem at all). I can make no attempt at the proof. Any help would be welcome.

Hi, I understand how any function could be decomposed into even and odd parts assuming the function isn't a purely even or odd to start with. It's just like saying that any vector in x-y plane could be decomposed into its x- and y-component assuming it doesn't lie parallel to x- or y-axis...

Hey guys, what would you say are the most important aspects of the job of being a nuclear reactor operator?

Found some old parts and was wondering if they look use able and what they could be used in. Apologies if I go against any of the forum policies.

Hi guys I have the length of a circumference, how do you divide it into equal parts given a certain amount of parts? For example, I want to divide a circumference into 78 equal parts, and the circumference diameter is 1 meter! Whats the length of each part? And how do you calculate it? (no...

Hey! :o A wheel of fortune is divided into $10$ equal sized parts, of which one of them brings the jackpot. A player wants to investigate the regularity of the wheel of fortune. He turns the wheel 20 times. Calculate the probability that he will get at least one main prize if it is a...

Hello, I'm just starting Zee's QFT in a Nutshell, I'm a bit confused about what he means by "integate by parts under the d4x". Can someone explain what he means by this? I understand how to obtain the Klein-Gordon equation from the free particle Lagrangian density, but not sure why he invokes...

Hello, Once reading about renal function I think, I read that there are actually parts from organelles circulating in blood that have a specific name. They also function as messengers. But I cannot find anything about it now, any idea?

Homework Statement The transverse velocity of the particle in Sections 2.5 and 2.7 is contained in (2.77), since By taking the real and imaginary parts, find expressions for v_x and v_y separately. Based on these expressions describe the time dependence of the transverse velocity. Homework...