Testing Definition and 589 Threads

Homework Statement Without a graph, test the suggestion that the speed, c, of the water wave is related to water depth, d, by: c ∝ d^1/2 No other data is given, this is suppose to be collected by myself but I am revising for a practical exam paper without having the data given. Markscheme...

Statistics doesn't come to me as naturally as math. I'm curious as to how to make a hypothesis test under the assumptions that the population standard deviation is unknown and using tables only. Here is my understanding. Given Suppose: H_0: \mu = \mu_0. Suppose also that: \bar{x}, s is the...

Hello all. Was wondering when I test for amps on my car's battery when sitting in my driveway why doesn't the car's electronics work when I hook up the battery via a serialized multimeter? The current should still, theoretically, go through the meter to the car's electrical system but it...

Hi, So I came across this article on the internet, and it was about the Equivalence Principle. So I were interested and read it all, and in the article it said that the EP might be only approximately true. What interested me more about the article was it said that any theory of quantum...

http://spectrum.ieee.org/podcast/biomedical/bionics/engineers-are-reinventing-drug-testing iPSCs Nina Tandon

Hello hello, I'm not looking just for an answer per say, but am also wondering the thought process in solving problems such as the following: Hopefully this doesn't take up too much of someones time. Determine whether the following equations are logically equivalent: 1) (∃x)( P(x) →...

Greetings, I have two signals, I need a way of testing whether they go above certain threshold voltages for a period of 0.5 seconds. This must be non programmable. I am a bit stumped o how to do it. I thought of having these signals go into an AND gate and then have that AND gate feed into...

Say I have a "large" population (larger than 1000) of red cards and blue cards which I want to find if it is evenly split (1:1 red:blue ratio). So I do an experiment and pull out 125 cards at random, and find that I have 50 red and 75 blue. Based on this experiment, what can I say about the...

Sorry to post a video - but seemed topical and entertainng... Cheers, Paul

Hi everyone. What is the metal thing on the top of the testing transformer (figure below)? It looks like electrode, but what is the use? I find it ubiquitous in many HV equipments.

Sir, I'm an undergraduate in 'Electronics'.Intending to develop a solar simulator with LED as the light source. It is understood that the spectral irradiance of sun can not be generated with the LED.So my plan is to light up a number of high power LED arrays of different...

The significance level of a test is the probability that the null hypothesis is rejected when it is true, right? And the critical region is the region that we reject the null hypothesis...so can the significance level be calculated by finding the probability of being in the critical region...

In this link: http://www.math.harvard.edu/~phorn/362/362assn3-solns.pdf Why isn't the significane level for number 5 just 0.01? Because we know that if the mean is 30,000 (the same as the mean for the null hypothesis), the value of the power function is 0.01... Thanks in advance

I think I’m a bit confused about what \alpha is. For the definition that is given, what theta really means when they say [tex]\alpha = max_{\theta \in w_0} P_{\theta} [(X_1, … , X_n) \in C]. I just think that it’s not really clear in my head, so is it ok if anybody explains/gives and example...

Homework Statement Alright, so I am a graduating senior studying Exercise science and physiology. I just had what we call "Client Testing" and ran my client (who was a collegiate athlete for the last four years and this year was her first year not competing or training) in the Bruce protocol...

Hey guys. As the title reads, I am a part of a research project and we will soon be testing a 100lbf jet engine. We take safety very seriously and want to take all the proper precautions in order to ensure everybody involved will come out of the experimentafely in case something goes wrong...

I'm trying to find a reasonably fast method for testing whether or not a point (x,y euclidean coordinate system) lies inside a (preferably convex, concave or complex - though different methods for each would be OK) compound polygon with edges consisting of line segments, arcs and/or elliptical...

"Cheap" Hydrostatic Testing Chamber As background information, I'm a computer programmer by trade but I want to get into underwater ROVs as a hobby because I need a hobby that doesn't involve sitting in a chair all the time, because Bob Ballard was one of my heros as a child, and because there...

Hi, I have a (hopefully) quick question about testing out of certain classes in college via proficiency exams. I am currently halfway through my first semester of freshman year and my current math courses are differential geometry and LA. I took a proficiency exam to skip calc 3 and got the...

Hi guys, litterely just signed up today and am liking the site. Ill cut to the chase. I am designing a concrete barrier to resist explosions, ballistics and heavy impact. Now while I am still an apprentice at structural engineering, My knowledge in mechanics and general physics isn't...

This is very interesting, is it the first proposed method (that is within reasonable energy for particle accelerators) to test space at the plank level? http://arxiv.org/abs/1207.7297 Testing Planck-Scale Gravity with Accelerators Vahagn Gharibyan Abstract: Quantum or torsion gravity...

Homework Statement \sum(\frac{2n}{2n+1})n2 (The sum being from n=1 to ∞). Homework Equations The Attempt at a Solution Used exponent properties to get (\frac{2n}{2n+1})2n. Using the root test, the nth root of an = lim n->∞(\frac{2n}{2n+1})2 = 1. However, the root test is...

Hello, I am new to the physical therapy field and I have a huge interesting in performance testing, especially VO2 testing. I am currently working on a project involving such testing. I was wondering if anyone knows the effects of unloading during VO2 max testing. For example, if a user...

Homework Statement Test the following integral for convergence: \int^{∞}_{-∞}\frac{dx}{\sqrt{x^{4}+1}} Homework Equations The Attempt at a Solution I was able to use the ratio test to show that the integral converges if and only if \int^{∞}_{-∞}\frac{dx}{x^{2}} converges, but I haven't...

Guys I am stuck with this can anyone help me??/ Suppose that 2% of all Olympic athletes use steroids or other performance-enhancing drugs. Because drug use is a serious violation of Olympic rules, the International Olympic Committee has implemented random drug tests. Let us assume that the...

Homework Statement A diffraction grating with 500 lines per mm is held directly in front of the lens of a digital camera, with a bright white light source 8m away. The image recorded by the camera shows both the light source and the spectrum created by the light source. We know that the CMOS...

I'm at the point in my graduate career where I must select an advisor within the coming months. I have about 4 professors narrowed down based on research interests and experience. One professor I get along with very well, but believe our academic interests are not exactly aligned. Another has...

Can anyone explain me how the load is applied to a metal specimen during tensile test? I am confused because I read in my textbook that after the ultimate stress is achieved and if the load is continued, then the metal specimen fails. But from the stress-strain diagram, we can see that the...

I need to test a coax cable assy for loss, resistance (AC&DC?) capacitance and inductance? Using a VNA in smith chart mode, how is it done? Do I sweep the coax (S11) with the other end open, shorted and then terminated? I know sweeping S21 will give me the loss @ freq of interest. Its the...

So l have got 16 data points and l would like to know if this data follows a uniform distribution. I have tried using the punif function in R, but l am not sure about the results l am getting. Can someone please tell me what is the best way and hopefully easiest way to see if data is uniformly...

ASTM provides standards for testing that's obvious enough if talk about the standard specimen profile; but idk that some specimen ,for instance round bars, are recommended to have a standard Dog Bone specimen but in case of deformed bar we don't have any special specimen. Tensile tests are...

Hello, Here's my question: When load testing a lifting lug that is welded to the ceiling, placing it under 5 tonnes of pull, using a chain block to tension and a web sling that is attached to the floor directly below, are you: A) Pulling 5 tonne down from the lug and 5 tonne up from the...

hi, in megger test of transformers which terminals we have to Earth and why? How this test is used to check insulation?

Introduction For me it all starts with what I agree is counter intuitive: The Speed of Light The speed of light. An innocuous phrase. Stating a seemingly obvious fact that light moves at a particular speed, in the same way that anything that moves has a speed. Yet what does it...

Hey everyone. I've been working on a axial flux permanent magnet DC generator to use on a 100W wind turbine(small I know), to charge 12v batteries in low wind speed areas. Now that it's complete, I'd like to determine the full power curve at different rpms. So far I've been running it on NO...

Homework Statement Hi, this is a stats question, hope I'm asking it in the right place. I am estimating an animal populations health based on it's weight to length ratio, I have a population ratio (10grams/cm) from 5 years ago and a sample estimate made from recently gathered data. I am...

We have jack in our lab that is suppose to be connected to ground, but the building is old, and we are not sure if we can trust that it is actually connected to ground. Is there a way to test the ground? If so, what is that way? Dr. Erzaask

I am designing my own Charpy impact testing machine and I am unsure what would be the best as well as relatively simple and affordable method I can use to accurately measure the angle the pendulum travels after it has broke the sample. I would also appreciate any complex and more expensive ideas...

A livestream video feed from the event has started and can be accessed via the CS homepage [1] or the corresponding blog on Wired [2]. Some background information about CS can be found on [3] together with a (very) short description on the TM65 [4]. [1] http://www.copenhagensuborbitals.com/ [2]...

Homework Statement Test the series for convergence or divergence\sum_{n=1}^{\infty} \frac{n!}{4.7.10...(3n+1)}x^n,\; x>0 The attempt at a solution I've decided to use the ratio test because of the factorial. L=\lim_{n\to \infty}\frac{u_{n+1}}{u_n} I worked it out and i got: L=\lim_{n\to...

i'm doing a task to find the amount of sodium hydroxide (NaOH) in a liquid soap. i have to use titration in it. how exactly would I do this? thanks

Hello, I am using a hydraulic shop press, to test the strength of acrylic weld joints. Here are my questions. -I replaced the pressure gauge that was included with a very precise digital gauge. The hydraulic piston that presses down has a removable circular head 2” DIA. Its neck is 1.48”...

Hi folks. Just looking for some input please. I have a dataset containing interval data (one dependent and 6 independent variables) and taken a random 90% sample (approx 300 observations). I've performed a linear stepwise regression on the 90%, in order to obtain a model to predict the...

In a parallel thread the scientific method became a subtopic, together with claims concerning "Intelligent Design"; a little elaboration may be useful. A discussion of the "scientific method" can be found in Wikipedia (I think that the summary is quite OK); a clear description can also be found...

Why does necking occur during tensile testing of ductile materials?

Literally running out the door, but came upon this. It seems to be a really interesting avenue to test GR vs. other gravity theories using hoped for GW detectors. http://arxiv.org/abs/1204.2585

Hello all, I'm in my final year of engineering so I'm required to complete a thesis as part of that. My topic is to investigate the wind loading on a typical conveyor belt + truss arrangement, because there's a lot of uncertainty in industry about drag coefficients etc. I've attached a model...

Hi, I am building a device. I need an in vivo procedure to perform the experiment. The experiment is based on shinning the red led light on to something just say finger. But I can't test it on any people or animals as of now. I need measure the measure drug concentration. So I need some kinda...

Alright. I know how incredibly inefficient this algorithm is, but I felt like giving this a whirl. #include <iostream> #include <cmath> using namespace std; bool prime(int x) { bool j = true; for (double i = 2;i == x;i++) { if (x/i == floor(x/i)) { j = false; } } return j; }...

I'm currently taking a Microprocessor course and we are adding to our breadboard week by week. The most recent add on was a UT6264CPCL RAM chip. Other chip specifications are given below in in 2. Homework Equations . My question is, how do we test to make sure that the RAM is working using two...