Error Definition and 998 Threads

I recently submitted a paper to a respectable journal. After submission, I discovered a few errors in my paper, one of which is quite serious. I have the corrected expressions and plots and I've checked that they are in agreement with the overall theory (as presented in other papers). My...

Homework Statement For the equation q = \frac{z(z+2) - 2DH}{z^2} q = -0.6 \pm 10\% , and z = 0.2. D and H are known exactly. I have to find the error in z that will give an answer of q = -0.6 \pm 10\% Homework EquationsThe Attempt at a Solution I have considered rewriting the equation...

Homework Statement Determine the minimum mean square error for the joint PMF. You will need to evaluate ##E_{X, Y}[(Y - 14/11\cdot X - 1/11)^2]##. Homework EquationsThe Attempt at a Solution The answer is ##\frac{3}{22}##, but when I work it out, I get ##\frac{203}{484}##. From my values, I...

Homework Statement Find electric field anywhere on the x-axis due two two point charges Q at (0,0,d) -Q at (0,0,-d) Homework EquationsThe Attempt at a Solution AttachedSomehow I am not getting the correct answer. I reviewed my steps with 4 people and we could not find the error! I'm...

Hi there, I am currently doing leak testing for a piece of equipment. In order to do so I have a flowmeter at the inlet and outlet (of what is essentially a long cylinder) and have air drawn through by a vacuum pump. Now, the problem is that even with no obvious signs of leaks the two flows...

Hey guys, I really need help with this, I do not understand what I did wrong in this experiment. I had a 30 cm ruler as a beam and some weights of 50 grams, 5 grams and 25 grams. I had a fulcrum which was 17 cm high. As you can see I only have measurements in 50, 5 and 25 grams. So I cut out...

Homework Statement I am writing a lab report for an X-ray diffraction. I have been attempting to come up with an equation for the error using formulas some people from college gave me and also some I found on wikipedia but I am quite sure I am doing it wrong. The only variable is the angle...

Does anyone know how to calculate the error between a function and its Fourier series representation as a function of the partial sums of the series? So far I haven't been able to find anything in the literature that talks about this. I'm also interested in looking at how well a Fourier series...

Homework Statement I am writing a lab report for an X-ray diffraction. I have been attempting to come up with an equation for the error using formulas some people from college gave me and also some I found on wikipedia but I am quite sure I am doing it wrong. The only variable is the angle...

When running the following code on Matlab: >> y(i) = y(i-1) + (0.5 * y.^3 * exp(t^2 + t))*h I get the error: ? Error using ==> mpower Matrix must be square. It seems fairly simple but I'm not quite sure what I'm overlooking. Any help with regards to what I may be doing wrong would be...

Homework Statement Derive an algebraic expression for the error in gravity due to the uncertainty in r. Use limit error formulas and show all steps. Assume that errors in G and M are negligible. Homework Equations g=GM/r^2 The Attempt at a Solution [/B] i use the error formula but not sure...

Homework Statement I am analysing intensities of some pictures. There are specific regions of higher intensities and so far i have managed to locate those regions automatically in Mathematica and the program returns the average intensity and standard deviation on this regions ("circles"), so I...

im using the if and else commands in c++ and for the else i want the program to print an error statement. how do i do this?

I have attached the lab right now I am stuck on proportional error in multiple variables I want to take the lab step by step so i can learn how to do calculate all the variables from now on. I have lab partners during the lab but I am completely clueless when I am working on it on my...

I've learned that the horizontal component is F cos angle not F sin angle, but I'm looking right now into the aqa physics a student book from nelson thrones, chapter 2.3 page 27, and it says that the horizontal components going to be made up of sin and the vertical out of cos... This is about...

In a lab measuring the charge to mass ratio of an electron I am having trouble with the error analysis. Specifically, this lab measured the radius of a curved path of an electron in a magnetic field (generated by Helmholtz coils with a a current 'I' running through them) with the velocity of the...

Homework Statement I need to find the roots of a given equation using the secant method and matlab. I have already found all the roots, but I am also asked to find the rate of convergence for the method empirically, meaning that they want me to find the order of convergence through the set...

Any help with this basic college problem. Homework Statement The following readings were obtained in an experiment to find the coefficient of viscosity of water n by measuring the rate of flow of water through a horizontal capillary tube. Diameter of capillary tube = 1.40 mm Length of...

sorry for spamming the boards with all these questions lol- i promise this is my last post regarding n body problems. how do i measure error? i can't really find much on this subject. i want to use adaptive stepsize in my n body simulator I am guessing for the n-body problem i base my error on...

Homework Statement Calculate the integral: ∫2x/(x2−11x+30) dx 2. The attempt at a solution I factored and got A/(x-6) + B/(x-5) = 2x/(x2−11x+30) Then I isolated and found A = 12 and B = -10 Then, after setting up the integral again, got 12ln(x-6) - 10ln(x-5) + C Unfortunately this is not...

Homework Statement I am trying to find the expectation value of <x2> of the following function: ψ[(x,t)]=(\frac{2am}{πh})[1/4]e[-a(\frac{mx^2}{h}+it)], where h is hbar and the integral is from -∞ to ∞ Homework Equations <x2>=\intx^2|ψ[(x,t)]|2dx The Attempt at a Solution The resulting...

Hi, If I poll 10 people (with a yes/no question), and all of them respond with 'yes', should I report the rate of 'no' answers (in the greater population) is "zero plus or minus zero", or simply be confident that it is "less than one in five"? I ask because using the "margin of error" (or...

Hi, I'm new in this space, I have a problem building a program with Fortran95 (I'm also new on this). The program it's really easy, I have to make a random generator using RANMAR subroutine here is the code: program random use aleatorio; use SAVEDATA Implicit none real, allocatable ...

I am getting the following error when i try to run my program: Operating system error: Cannot allocate memory Allocation would exceed memory limit Any thoughts about that this is and maybe any suggestions about how to resolve the issue??

Hi All, So here is an error analysis question for you all: I am measuring the temperature of an object at three positions simultaneously. They are type K thermocouples so their individual error is 0.75% of their reading. However, I can also take long term data which shows that...

Hi, On p.4 of "A First Course in General Relativity", Shutz says that we redefine the units of time so that the new unit of time is the meter, where one meter is "the time it takes time to travel one meter". He then argues that: ## c =...

Homework Statement I am conducting an experiment to determine the specific heat of a certain metal using a typical calorimetry experiment (using a polystyrene cup). I have been asked to list sources of error and quantify them in relation to the total error in the experiment - I have thought...

Hello all, as a recent graduate and a new teacher, I am living in Honduras and teaching the sciences in a high school setting. I did not study to be a teaching by got my bachelors in Spanish and Physics. I am working at a bilingual school and my resources are extremely limited. My question is...

I'm really exhausted mentally, so it'll be really helpful if someone can tell me where I made a mistake. I'm rotating surfaces, and with that, I had to solve this integral: $$=\pi \int \sqrt{64-3x^2} dx$$ $$=\frac{\pi}{\sqrt{3}} \int \sqrt{\frac{64}{3}-x^2} dx$$ Let $$x = \frac{8}{\sqrt{3}}...

I try to import a sab. Modeltyp in Ansoft 15. but i receive an error that translation for the model is failed or saved file is from a later version. how can i fix the problem. Thank you .

Homework Statement Find the Uncertainty of the Total Resistance of two (2) parallel-connected resistors: R1 = 2.2 kΩ ± 5\% \ ;\ R2 = 1.8 kΩ ± 20\%. Homework Equations We know that resistors in parallel are: \frac{1}{R_t}={\frac{1}{R_1±\delta_{R_1}}+\frac{1}{R_2±\delta_{R_2}}} This...

Homework Statement If you didn't already, download splineFunctions.zipView in a new window. This contains the splineE7.p and splinevalueE7.p function files. The syntax is as follows: If Xdata and Ydata are vectors with the same number of elements, then four various splines can be created as...

Homework Statement This is a statistics as applied to astronomy problem. My stats knowledge is horrible. Anyway, the problem: For several hundred objects, I have a number of different properties for which I have a measurement & associated measurement error. For example, flux density and...

Hello. What would happen if there's a mistake in the pull up circuit where nMOSFET is used in the pull up circuit while the pMOSFET is used in the pull down circuit? What would happen to the action of the inverter, output voltage range and characteristics? I have been trying to find some...

From Matter & Interactions Volume 3: Am I correct that there is something wrong with the statement of the velocity vector here? The components are missing in the statement of the problem, yes?

Hello to all Experts in Adsorption Physics! Here is a research paper, stating that water adsorbed in a mineral called bentonite can store as much as 30 kJ/g. According our research and findings with such water based latent heat or phase change storage systems, there seem to be a fatal error...

Let's say a student does a simple experiment where she conducts 10 trials at each x value (at each value of the independent variable). She collects data over 30 x values, giving her 300 total trials. For each of the 30 x values, she averages the 10 y values and she calculates the standard...

Hi there- I'm trying to check an array for ascending order and if not to print out the number that is out of order by using a function. I solved it by not using a function but when I've tried to use a fxn for some reason it tells me that in my call for the fxn the numbers "argument of type int...

Homework Statement A single phase half wave rectifier produces a DC signal ##V_{DC} = (4.6 \pm 0.78) V## and AC signal ##V_{AC} = (0.22 \pm 0.036) V##. What is the error on the efficiency? Homework Equations Functional dependence, propagation of error: ##\sigma_f = \sqrt{...

Hi I am using relap to study a blowdown transient. If I let it run it with actual heat fluxes, the program terminates with error message saying thermodynamic property error with maximum time step. Reducing the time step delays the onset of the error by a fraction of a second. Runs much longer...

Hello all, I am doing a SOL 600 analysis but Nastran gives me an error of "zero thickness" in some elements. Obviously, I checked those elements and they have properly defined their properties so I don't know what can I do. I've done a lot of linear and nonlinear static analysis in that...

Homework Statement So I am calculating the error for something and I am getting really weird values. So I know that the value for the Inductor is 24.97 +- 0.005 mH and that for the capacitor is 105.7+-0.0005 nf. So I am finding the value for the resonant frequency Homework Equations...

Homework Statement The maximum error in the measurement of the mass and length of the side of a cube are 3% and 2% respectively. What is the maximum error in the measurement of density? (The questions has options as:- (a)3% (b)5% (c)6% (d)9% (e)12% Homework Equations Density(ρ)=...

Homework Statement The density of a cylinder is calculated from the following data: ##m= (2.8±0.8)g## ##d = (2.2±0.1)cm## ##h = (4.0±1.0) cm## What is the error on the density, before rounding, in ##\frac{g}{cm^3}##? Homework Equations ##V = \pi r^2 h = \frac{1}{4} \pi d^2...

This problem deals with finding the coefficient of friction between an object and a slope. It gives an object with mass m, sliding down a hill with a slope of θ at a constant velocity. I got mgsinθ=fksinθ. However the book shows mgsinθ=fk. The kinetic friction force and the force down the slope...

Dear Fellows, If we fit our data to a quadratic equation then What is meant by standard error for linear and quaratic coefficients ? I know that standard error is the standard deviation from the Sampling data. But for individual coefficients what is its interpretation ? Best Wishes Masood

Hi everyone, I recently purchased a Sonobond Ultrasonic Welder for Plastics (MP3512 w/ Generator SL35-900). After setting it up with the compressed air system and a voltage converter (I'm in the US), I turned the generator on. On the display, I got an "ERROR FREQUENCY." I thought it was...

How do I calculate the percentage error between a guess of a position in 3D space, and the actual position. For example, if I am allowed an error of 100mm in the x, y, and z directions, in a 5m x 4m x 3m volume, what is the maximum percentage error allowed? Can I just do...

Error running optimization. Inputs must be a scalar and a square matri I am trying to use fminunc using optimtool. But i got the error Error running optimization. Inputs must be a scalar and a square matrix. this is the function i typed in the editor. function F = fun(x) F =...

Hi, this is not a homework and my problem is much bigger for me to give full details here. I came across this integral \mathcal{I}(\xi)=\int^{\xi_c}_{\xi}{\rm d}\xi^\prime\exp\left[\sqrt{2}\sigma\,{\rm Erf}^{-1}\left(1-\frac{8\pi}{3}{\xi^\prime}^3\right)\right] where Erf^{-1} is the...