Test Definition and 1000 Threads

North Korea apparently detonated a nuclear weapon - again. M5.3 Explosion - 19km ENE of Sungjibaegam, North Korea http://earthquake.usgs.gov/earthquakes/eventpage/us10006n8a#executive 2016-09-09 00:30:01 UTC 41.298°N 129.015°E 0.0 km depth...

Hi all. What does the voltage rating in each category I/II/III/IV actually mean? For example, my multimeter is Cat III rated to 300V. Is this RMS? Peak? Peak-peak? Our supply here is 230V RMS AC, but this means the momentary peak is about + and - 330V (relative to neutral/ground) and the...

I have $$\sum_{n = 1}^{\infty} \frac{2^n}{n^{100}}$$ and I need to find whether it converges or diverges. I can use the ratio test to get: $$\lim_{{n}\to{\infty}} \frac{2^{n + 1}\cdot n^{100}}{2^n \cdot (n + 1)^{100}}$$ But I'm not sure how to get the limit from this. I know the limit of...

First off, I know very little about physics and have only taken classes in high school years ago. I'm a car fanatic and I'm mainly joining this forum to settle a debate I'm having with one of my friends about turbo cars and boost leak tests. For those who don't know, in an automotive...

That doesn't artificially inflate your results. So I'm curious to see how accurate it is (perceived to be) among the 'general population'. 43 minutes to solve out 38 pattern recognition problems. I scored 113 (SD15). Way less than what I usually get in this kind of online IQ games (130s/140s)...

Hi guys, I am performing drop-weight impact tests on concrete slab. I have designed a bullet made of high tensile steel and I am interested to recorded the acceleration, then convert it to impact force. For this purpose, I need to implement an accelerometer on the bullet. I have tried two...

Perhaps a silly question, but... As I understand it, if a particle has a 1/2 spin, it must be spun 720 degrees for it to arrive at its original orientation. What experiment spins a particle like this? Has there been one that actually spins a particle 720 degrees and checks its orientation? Or...

I'm really confused about this test. Suppose we let f(n)=an and f(x) follows all the conditions. When you take the integral of f(x) and gives you some value. What are you supposed to conclude from this value?

I was examining the AKS and discovered this conjecture. Please prove the following true or false. Let n be an odd integer >2 then n is prime IFF $\left( \begin{array}{c} n-1 \\ \frac{n-1}{2} \\ \end{array} \right) \text{ $\equiv $ } \pm 1$ mod n

The limit comparison test states that if $a_n$ and $b_n$ are both positive and $L = \lim_{{n}\to{\infty} } \frac{a_n}{b_n} > 0$ then $\sum_{}^{} a_n$ will converge if $\sum_{}^{} b_n$ and $\sum_{}^{} a_n$ will diverge if $\sum_{}^{} b_n$ diverges. Does this rule also apply if $L$ diverges to...

Good afternoon, I'm glad I've joined this forum. Here's my doubt: I have a serie of values in a table like this: Case 1 34 55 Case 2 23 10 Case 3 55 40 etc... the 34 means the observed value, and the 55 the control group, and so on. It's easy to do the test of course if... The problem is: if...

I have this series: $$\sum_{k = 1}^{\infty} {4}^{\frac{1}{k}}$$ To solve this, I am trying to compare it to this series $$\sum_{k = 1}^{\infty} {4}^{k}$$ So, I can let $a_k = {4}^{\frac{1}{k}} $ and $b_k = {4}^{k}$ These seem to be both positive series and $ 0 \le a_k \le b_k$ Therefore...

Homework Statement Hi everybody! Our experiments teacher asked us to perform a reduced chi square test in order to estimate how good a model fits to our measured data. The experiment was the melde's experiment (vibration of a string) and we measured the frequency ##f_n## for ##n=1## to ##9##...

Assume that you are being sent back in time. You can choose the exact time period, but it has to be more than 200 years ago. You cannot bring anything with you. How would you use your current knowledge in order to survive? Would you be able to get rich/famous/powerful? Note: you cannot learn...

https://psychology-tools.com/empathy-quotient/ Also watch this video: How it was? What was your empathy quotient? Did you yawn? :)

Homework Statement Hi everybody! In the context of a physics experiment about radioactivity, I am asked to perform two distributions (poisson and normal) and run a chi-square test for both of them in order to define which one is the most adapted to the histogram (see attached picture)...

Hello, I am want to prove that: $$ \sum_{1}^{\infty} \frac{1}{n^{2} + 1} < \frac{1}{2} + \frac{1}{4}\pi $$ Cauchy's Convergence Integral If a function decreases as n tends to get large, say f(x), we can obtain decreasing functions of x, such that: $$ f(\nu - 1) \geqslant f(x) \geqslant...

Hi everyone. I am totally new to statistics so my question may or may not be simple! I know that for the data fitting we can do a chi squared test like: \begin{equation} \chi^2 = \Sigma \frac{(f_{data}-f_{model})^2}{(error_{data})^2}\end{equation} So I have been doing this for a while, but now...

hi, If you look at my attachment you can see that the book express that for the situation of x=+,-(1/L) we need further investigation. It means being converged or diverged is not precise. I would like to ask: Is there remarkable proof that if x=+,-(1/L) convergence or divergence is not...

I'm a little confused by what exactly determines if a reaction is reversible or irreversible. I thought I have heard that if the delta G of a reaction is negative (which means it's spontaneous), that it's then irreversible, but that doesn't make a whole lot of sense when I think about it...

what is the best book to pass GRE-PHYSICS test ?

Some metal give two yield point in stress strain diagram. One is called Upper yield point and Lower yield point. Why lower yield point is considered as more reliable. I can think of Upper yield point is much more dependent upon experimental apparatus settings. So why lower yield point is much...

I have drawn my circuit in Proteus, and in the simulation it can run, but when i used GL 12 test board to test my circuit, it can't run. And i reallize that i don't know where is the ground in the test board. Can you guy tell me where is the ground ?

Hi everyone, I suffer from Delayed Sleep Phase Disorder: https://en.wikipedia.org/wiki/Delayed_sleep_phase_disorder I've been taking sleeping pills for it for years (without them, I'd never be up in time for work) but have recently become concerned about adverse consequences of long-term use...

Hi there, I've recently start learning methods for determining whether or not time series are stationary. The first method I'm trying to learn is the 'Dickey-Fuller Test'. This test uses a time series modeled by an AR(1) process. The key is to find whether or not this process contains a unit...

What test can we perform on a vector field to determine if there exist vector field(s) that describe its inverse curl?

In a two-tailed test, the value of the test statistic is 2. If we know the test statistic follows a Student’s t- distribution with P (T>2) = 0.03, then we have sufficient evidence to reject the null hypothesis at 0.05 level of significance. I want to say True but I think I'm overthinking the...

Imagine a test particle (say a golf ball) just floating in flat space-time. Now have a sunlike star instantly appear some distance away. From the perspective of a distant observer, (using very distant background stars for reference), the golf ball will be shifted towards the star a certain...

Hello all, I am working on a few test scripts to test the life of a hydraulic cylinder. (It is a mechanically operated cylinder and has a positive displacement) The testing will involve thousands of continuous pump and retraction operations, due to which the temperature of the piston seal and...

Breakthrough Starshot is an ambitious project that aims to use a superlaser to push a tiny craft up to 0.2 c https://en.wikipedia.org/wiki/Breakthrough_Starshot At such speeds, it would be possible to perform a macroscopic test of the longitudinal acceleration, provided the craft has an...

Hi all, I am designing a three phase 11000/433 Volts Delta/Star 50 Hertz transformer in Ansys Maxwell. It has 792 turns in 6 layers on HV side (132 turns per layer) and 18 turns in 2 layers (9 turns per layer). The resistance as I have calculated is 0.1325 ohms per phase of HV winding and 5.57...

http://free.ultimaiq.net/numerus_basic.htm

Hi, I want to test this radiation detector http://www.teviso.com/en/products/radiation-sensor-rd3024.htm The problem is we don't have strong nuclear radiation sources or even weak ones , can i mimic the radiation ?? For example can i use Microwave sources or RF field or other radiation sources...

Homework Statement Let f(x)= (1+x)4/3 - In this question we are studying the Taylor series for f(x) about x=2. This assignment begins by having us find the first 6 terms in this Taylor series. For time, I will omit them; however, let's note that as we continuously take the derivative of this...

For the locked rotor test I have these values, P1 = 620W Stator line voltage = 32V Stator line current = 8.4A To calculate active power/phase, Po = (P1+P2)/3 But I don't have P2, Is P1 maybe equal to P2 ?

My daughter is a Sophmore in high school and is taking Calculus with a current focus on Trig. I am trying to help her study but this stuff is way over my head...but I am trying! Can anyone help me with this? Here are a few of her study problems that we cannot figure out. Can you help me to...

It looks like there is no replacement for the VFETs that were made by Yamaha or Sony. So, if a amp uses these output transistors and they have failed then the amp is not repairable. The amp in question is a Yamaha B-2. One side is working without issue. The other side is not working. The output...

Hi everybody! I have another question about integrability, especially about the limit comparison test. The script my teacher wrote states: (roughly translated from German) Limit test: Let -∞ < a < b ≤ ∞ and the functions f: [a,b) → [0,∞) and f: [a,b) → (0,∞) be proper integrable for any c ∈...

I just took a calc 2 test and got 3/8 points on several problems that asked you to show convergence or divergence. The reason being that I didn't use the correct test of convergence? The answer was right, if you get to the point where you know the series converges, then why does it matter which...

The recent thread of @ProfuselyQuarky reminded me of this fun puzzle. It's called the Wason's Selection Test. I stole it pretty obviously from the following website, so do check it out: http://www.philosophyexperiments.com/wason/ About 75%-80% get this wrong. You are a quality control...

Hi there i am trying to test RF Waveguides and testing them. Something does not look right to me. i am using Freq range, data points, power and avg option is there anything special we use on VNA for testing Waveguides. Regards, Faheem

Homework Statement The Attempt at a Solution First up, part a. The first one is really simple. The generator is working at its rated voltage of 13.8kV, right? So, would the required field current not be just 225 Amps? Next, part b. To sort of explain what's going on, I first found the...

Homework Statement \lim_{n \to \infty}\frac{(-1)^{n+1} \cdot n^2}{n^2+1} Homework Equations \lim_{n \to \infty}a_n \neq 0 \rightarrow S \ is \ divergent The Attempt at a Solution I tried L'Hopital's rule, but I could not figure out how to find the limit of that pesky (-1)^{n+1}. Edit: This...

Hi Guys, I am working on a Carver model M-1.0t stereo amp. There is no AC voltage to the input transformer primary. The AC input is controlled by a Bi-Directional Triode Thyristor. This is the data sheet. http://www.datasheet.hk/view_online.php?id=1927120&file=0465\sm16gz41_6629879.pdf This is...

Has there ever been an experiment to support the principle assumption of relativity? For example an experiment where an atomic clock is sent on a probe to , let's say, Pluto. We on Earth get transmissions of the time on that ship and, after taking account of the light travel time delay, we...

Which of these converge? 1. 5n/ (2n-1) 2. e^n/ n 3. e^n/ (1+e^n) Attempt: 1) lim n-> ∞ 5n/(2n-1) = 5n/2n = 5/2 ≠ 0 so diverge? 2) Change n to x e^x/ (1 + e^x) Antiderivative: ln |1 + e^x| lim t->∞ of ln |1 + e^x| ln |1 + e^∞| - ln |1 + e^0| Got stuck here 3) Help :(

n^2 - 1 / (n^3 + 6n) If I use the nth divergence test, I plug ∞ in (limit as n -> ∞) for n and since the degree on the bottom is larger I get 0, which means it converges. However, if I use the limit comparison test and compare it to: n^2/n^3, which = 1/n, which diverges -> n^2 - 1 / (n^3 + 6n)...

For my senior project i plan on litening a vw rabbit car. 1981. Any software that i could uuse to model the care and provide great data on how i could improve the safety after i cut it up to lighten it? Thinking adding roll bars or something.

I´m really struggling to find the shear force here. 1. Homework Statement Hight h of a specimen = 100mm and diameter is 54mm. Max force F=144,6 N and deformation is δ=5mm Homework Equations I have to find ε=δ/h Area of specimen before deformation=54mm*100mm=5400mm σz =(F(1-ε))/A Shear force =...

Homework Statement where does the 1(circled part) come from ? is it a mistake ? Homework EquationsThe Attempt at a Solution