Testing Definition and 634 Threads

My attempt: a) I am not really sure I understand this option fully but my answer will be this one is only applicable if the sample size is large and central limit theorem can be applied so (a) is wrong b) The test statistic has "same distribution" to what? My opinion is (b) is wrong because...

##H_0##: The probability of an obese person using chopsticks = the probability of a normal-weight person using chopsticks ##H_a##: The probability of an obese person using chopsticks ##\ne## the probability of a normal-weight person using chopsticks "Partial" Chi-Square Test: I focused only on...

I am designing a system to test floors, called the "Robinson-Type Floor Test". I have the basic design below, but I'm having trouble determining how exactly to spec the motor here. The large pulley on the rotary shaft is 12in in diameter and the small pulley on the motor is 3in in diameter. At...

https://peterliljedahl.com/wp-content/uploads/Myth-of-Objectivity-2.pdf

A group of astrophysicists have developed a method to measure the value of the cosmological constant using the dynamics of the Local Group: Constraining Dark Energy from Local Group dynamics

Hello, I'm testing about burnable poison depletion with mcnp6. I'm using m1 92233.82c -7.91619E-01 90232.82c -8.75802E-02 8016.82c -1.20800E-01 for fuel and m12 64152.82c -1.39023E-03 $ gd-152 64154.82c -1.53529E-02 $ gd-154...

I have a battery powered wireless product in a plastic IP68 enclosure with no exposed metal that attaches to a sensor through a cable that is about 6 feet long that again is completely encapsulated with no exposed metal. I want to get a CE Mark certification and since this for outdoor use my...

Type-2 diabetes patients generally display higher levels of glucose circulating in their blood. While type-1 is considered a lack of insulin disease, in type-2 it is considered that insulin may be present, but it is not working properly. It is called Insulin-resistance. Most of the drugs for...

Hi guys, I have heard a lot of claims about ChatGPT and how it is going to put a lot of people out of work. I have a friend who is a teacher of humanities and he is fearful of losing his job in the long term. People seem to be in awe at the thing and think it understand what is saying. So I...

I'm trying to make a DIY 'ECG' machine, except that it'll only record heartbeats on a piece of paper. Basically the piece of paper will be wound round a cylinder like object, which will be being spun slowly by a motor. A pencil at the end of a stick or something will be writing to this piece of...

Hi, a teacher and I have been looking for websites to take Math/Physics exercises from, put them together as a test, print it and pass it to students. I know there are many websites that give you tools to write your own exercises (mainly many LMSes). But we'd like to pick exercises already...

Hello Everybody, Im doing my lab report on Fatigue testing for a Single Edge Notched Tension (SENT) sample and need to plot ΔK vs da/dN for a series of a vs N readings at different R and maximum stress values (attached in the picture). I've just been given one equation for Ki and told that I...

##p(x≤11)=1-[p(x=12)+p(x=13)+p(x=14)+p(x=15)]## ##p(x≤11)=1-[0.128505+0.266895+0.3431518+0.205891]=1-0.9444428=0.0556## ##⇒p(x>11)=0.9444## ##p(x≤10)=1-[0.042835+0.128505+0.266895+0.3431518+0.205891]=1-0.9872778=0.0127222## Since, ##p(x≤11)=0.0556> 0.05## then it falls on the Accepted region...

Hello all, I am looking for some design ideas. I need to do some compression testing and here is my testing platens: The platens are small (5mm*5 mm) and my samples are even smaller with the cross section of 3mm*2.4mm, so it would be difficult to both position them within the platens and align...

Proof: Consider all primes ## p\leq\sqrt{701}\leq 27 ##. Note that ## 701=2(350)+1 ## ## =3(233)+2 ## ## =5(140)+1 ## ## =7(100)+1 ## ## =11(63)+8 ## ## =13(53)+12 ##...

So I have two columns of data, One containing experimental values and the other having expected values. So I read that chi-squared test and Anova Tests can be used to compare two set of data. My main aim is to quantitatively know how different these two sets of data are, so are these two tests...

I would like to test the insulation of a transformer using partial discharge analysis. Testing insulation between the primary and secondary is pretty straightforward. I short the primary as well as the secondary, apply voltage across the two, then take my measurements. I also need to test the...

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It is a sensor with a fixed surface and a prescribed displacement on the opposite To remove this message error, I have tried to Increase iterations Refined mesh Applied parametric studies And some other ideas from forums However it still cannot be solved It also has a warning of MUMPS out...

This is pretty interesting. It sounds like GE and the Air Force have been able to make some good improvements recently...

I want to understand how an experiment is carried out to test violations of the CHSH inequalities. I have read Wikipedia and one popular book on quantum mechanics. The Wikipedia article is too short and incomprehensible to me; in addition, the description from Wikipedia and from the book is...

An adventurer who likes to explore desolate places in the South-West USA, found some scientists testing a prototype robot at a sinkhole in a desert in Utah. As the discussion in this video indicates, the later developed robot may be used to explore pits on the moon.

For my internship I have to test and certify a Marine diesel engine. We are trying to run a few tests in our workshop, but this obviously means we can't use the sea or a river as cooling. We bought an IBC tank, which can hold a 1000 liters of water. The water from the tank will be running...

From z-table, I get the critical value of z is -1.282 Will the rejection region be z < -1.282 or z ≤ -1.282? If I calculate the test statistics and it has value of -1.282, would I reject or accept null hypothesis? Thanks

We (company I am interning for) are meeting with various suppliers in efforts to find a new source of vacuum pumps for our brake boosters. We are looking to make a switch to an electrical pump versus the mechanically-driven pump we used previously. One of the issues we are having with this is...

I am working in a student satellite team and we are working on development of star tracker. So for the testing of it, we will simulate some star images on LCD, but the problem is that rays coming into the star tracker should be parallel as original stars are at infinity. So my question is that...

[Mentor Note: thread split off from a different thread] https://www.physicsforums.com/threads/heavier-objects-fall-faster.1002022/ Since seeing this thread yesterday, I have been trying to derive the time equation for the collision of two masses due to Newtonian gravity. Unfortunately, this...

Hello. Microphone is a simple device and its mechanism is also simple. The device converting sound waves into electrical energy is mic. But I am little curious about how microphone manufacturer company check their mics before selling? Means Can I test my mic at home using standard process? I...

Hey! :giggle: Some people assume that a specific car model does at least $\mu_0=120$ km with $1$ Lt benzin. $10$ independent tests give the following results: $$104, \ 96, \ 80, \ 100, \ 108, \ 100, \ 112, \ 120, \ 130, \ 132$$ (a) Give the Null Hypothesis $H_0$ and the alternative...

Hi, What can be done to avoid trupped bubble air at the top of a pressure vessel without upper hole during hydraulic testing? Also, once the bubble exist what can be done to release it? Thanks

I am test my knowledge of differential forms and obviously I am missing something because I can't figure out where I am going wrong here: Let ##C## denote the positively oriented half-circle of radius ##r## parametrized by ##(x,y) = (r \cos t, r \sin t)## for ##t \in (0, \pi)##. The value of...

This is an MCLV-2 development board from microchip, with it got the Hurst motor as shown below The problem is that the shaft is smooth i cannot connect the loads etc. So, I want to clarify the below points a. What type of connectors i should look for and which websites will have the...

Hey there .After making a conjecture whether in math or physics how do I check if it is on the right way?By applying special cases?About making the conjecture?Just connecting objects and forming relations?The proving part is a bit difficult but what about it?Is it also about a bit of doing it in...

[Moderator's Note: Thread spun off from previous thread in General Discussion since it is more specifically about particular scientific theories and how to test them against data.] So in your opinion, everything in the list below is quantitative, not qualitative...

I tested the first function with the Cauchy Riemann equations and it seemed to fail that test, so I don't believe that function is analytic. However, I'm really not sure how to show that it is or is not analytic using the definition of the complex derivative.

Answer : I understnad why x(< or = ) 2 but I do not understand why we use 16 instead of 17 for the second range? When P(X>=16) > 0.005(which is the level of significance). Thank you for all the help given :)

Due to COVID my college has been conducting online examinations. I have not done as well as I would have liked and this is entirely my responsibility. However, given the absence of proctoring I am aware that significant cheating has occurred and while my absolute score is completely in my hands...

Hi ... air resistance is the reason that objects of different mass fall to Earth at different speeds. In a vacuum all objects fall to Earth at the same rate regardless of mass. OK - I get it but all the experiments that illustrate this tend to rely on tall buildings or massive vacuum chambers...

Hi. In an Elitzur–Vaidman bomb tester, will the guiding wave be different in a situation with a live bomb compared to one with only a dud? And if yes, how does the bomb interact with the guiding wave? Because usually it is described as a pointlike device that only explodes when hit by the...

Are there video files that I can download to test whether my configuration of VLC (on Linux, Fedora) will be able to play DVDs from various regions? Or must I have physical DVDs to test this?

This is Ackbach posing as test, to make sure I can post easily in the right places as a registered user.

Some governments seem to think that testing for the virus is not central to controlling its effect on the population. So far, nearly all I read about the statistics are based on people who actually present with the symptoms. If you are not a 'key worker' then tests in the UK are not available...

Germany has been virus testing in groups of 10. In a high risk population where p=1/100 this requires, on average, 196 tests to test 1000 people. In a moderate risk population, it requires 109 tests to test 1000 people. But if they were to test in groups of 32 in such a population one would...

I often read that whenever a new fossil is found (like a bone fragment or skull fragment etc) they trace it back to either some animal or human , now mostly (and before DNA testing was possible) this was done I suppose by visual inspection and "radiocarbon" dating to put the fossil in a...

Hey all, I bought some LiTaO3 crystals in order to test the pyroelectric effect. Unfortunately I am not detecting any pyroelectric voltage during heating. According to the vendor, the Z-axis is lengthwise as shown in the attached diagram. I then put the crystal between two metal electrodes...

So something weird just happened along the way in my experiment, here is a little background of what I'm doing. I have created a roughly 3x5mm inner diameter rectangular shaped channel for MHD liquid testing for one other project of mine, it's a simple conduction type MHD pump where the...

Hi, I have some set of data and I want to use Hypothesis Testing to discriminate between two hypotheses: H0: My data follows a Gaussian distribution with a given mean and a given std (the actual values are ugly, so let's say mean = 0 and std = 1). H1: My data follows a Gaussian distribution with...

Hello, I am looking to mechanically test different variations of the same sandwich panel. The sandwich panel will consist of a honeycomb core made from recycled PP, with skins made from Flax tape combined with resin. The end goal of these tests is to investigate how the material property...

Hi Recently my company has wanted to conduct waste testing to determine the composition of the wastes in concentration or wt%. This testing will help us to determine whether there are any excess chemicals in the feed of the process, which in turn can also be used to identify the effective...