Estimate Definition and 350 Threads

Hi Guys, I have a problem about the starting current of a pump's electrical motor. I have the working condition of the pump (torque, power, speed, P and Q) But how could I calculate the start up current of an IEC standard motor? Seems I has to gather a Torque-speed curve from the...

Hi, I need help understanding how do I use t-distribution to estimate the tα/2 . Also what is meant when it asks "verify your result with empirical rule"

[b]1. we have 1 road length 10km x 8m is given to do for 6 months. the works was given a volume of Embankment 80,000m3 and the volume of subase 24000m3 and the volume of base course 16000m3. so what can we do to make the road and estimate the cost and describe the work of tool to use. (just...

Homework Statement A piece of metal at 80°C is placed into 1.2 litres of water at 72°C. This thermally isolated system reaches a final temperature of 76°C. Estimate the overall change of entropy for this system. Homework Equations (delta)S = Q/T The Attempt at a Solution...

In the thread in P&WA on the issue of the oil spill, I expressed my skepticism that the rate of the spill could be accurately measured via analysis of underwater video clips. That skepticism was strengthened by the recent statement by Prof Steven Wereley, the originator of the first such...

Homework Statement I have to prove that the solution of an ODE can be continued to a function \in \mathcal{C}^1(\mathbb{R}) . The solution is: e^{-\frac{1}{x^2}} \int_{x_0}^x -\frac{2e^{\frac{1}{t^2}}}{t^2} dt It is clear that this function is not defined in x=0 . Its limit for x \rightarrow...

i have a first order nonlinear differential equation y'=-sin^2(kx+y)/kx the boundary condition is y(x=0)=0 here k is a real positive number i want to estimate the behavior of y as x goes to infinity how to do this? any book for reference?

Hi, this is a problem I am trying to do: So I found that at 3dB, V0=0.7079Vi and I wasn't sure if I should use real numbers or complex numbers, I did both, I'll show the real one: Vo/Vi=0.7079=R/(R+1/wc)=Rwc/(Rwc+1)...I can solve for w, but this will only give one answer, when I use complex...

Homework Statement Estimate sin4 accurate to five decimal places (using maclaurin series of sin) Homework Equations The Attempt at a Solution Lagrange error bound to estimate sin4° to five decimal places( maclaurin series) 4°=pi/45 radians |Rn(pi/45)<1*(pi/45)^n+1/(n+1)...

1. Urula is doing a project and has caughed, tagged and released 50 possums. Estimate the population of the possums in the park. Three nights later she captures a sample. 2. If ursula captures 20 possums and 4 of them are tagged, what would her estimate of the local possum population be...

Homework Statement I'm completing a homework for Young's Modulus and one question asks to estimate the elastic limit for the wire which was used. I can see where this approximately is on the graph I have drawn. When the question asks to estimate the elastic limit, does this mean to...

Homework Statement I am trying to calculate the estimated final velocity of a R/C hovercraft i am trying to built. The craft's weight is 6lbs and it is powered by a electric ducted fan that produces 21.3 ounces of thrust. Assuming this craft is actually hovering (no friction with the ground)...

Homework Statement A telephone wire of diameter 1mm is suspended 10m above the ground. Estimate its capacitance to Earth per unit length Homework Equations The Attempt at a Solution I've tried to solve the problem by using the formula for a cylindrical capacitor and got the answer...

They didn't have Carbon 14 and I think fossil tree rings (dendochronology?) is a modern method so where did they get their millions of year from?

Although a complete cost analysis is much more complicated, the particular question only requires the following: an energy cost estimate (in terms of $/Joule). This was directed to be done by taking volumetric or mass based costs of each fuel as well as the associated energy conent or energy...

Hi, i worked through several examples where the ground state energy of a particle in an arbitrary potential V(r) is estimated with Heisenberg's uncertainty relation. In these examples they prepare the Hamiltonian for the particle. For example the Hamiltonian for a particle in a harmonic...

T/F=Transformer usually T/F is used according to the load of the area, street etc. How they estimate that 50 KVA transformer is enough for this load,street? any formula or method please explain ::Thanks

Hi! I need help with the monte carlo integration: reliability of the error estimate for functions that are not square integrable. I'm supposed to investigate this topic.*Hence my first question is what is a function that is not square integrable? I found that such a function is 1/sqrt(x) on...

summation from 1 to infinite: (5n)/(n^2+1) What is the maximum amount of error of s4 as compared to the infinite series? error=S-Sn<bn+1 I got S4=-14/17 and S5=-25/26 but how you suppose to get S? i though you can't tell what a alternating series converge to

Hi all, I have implemented a nonlinear lifting line method to estimate lift/induced drag of a typical wing. This method utilizes 2D lift coefficient data, and uses a numerical technique to solve the nonlinear equations. The program I have written in MATLAB is working, though I would like to...

Homework Statement (a) Expand f(x) as a power series f(x)=\frac{7}_{\sqrt[4]{1+\frac{x}_{14}}} Which I converted to... 7 - \frac{1}{8}*x + \sum^{\infty}_{n=2}7*(-1)^{n}*\frac{1*5*9*...*(4n-3)}{4^{n}*n!}*(\frac{x}{14})^{n} (b) Use part (a) to estimate 7 / (1.1)^(1/4) correct to...

Hi all, I'm using NS2 to simulate wireless sensor networks. I want an estimate of the initial sensor battery energy. I know that each sensor node uses 2 AA batteries. I have no assumptions about the current. I search for a while on the internet but couldn't find a direct estimate. Thanks...

Homework Statement Use differentials to estimate the amount of tin in a closed tin can with diameter 8cm, and height 12cm, if the tin is 0.04 cm thick. The way I did this was to subtract the Max volume by the Enclosed volume. Max Volume is pi(4)(12) Enclosed Volume is pi ( 8 - 2(0.04) )/2...

Is there a way to estimate the mass of a star using Spectral Class and absolute magnitude? If you can't then what info do I need in order to so. Thanks, Dan

at design energies 14TEV collisions?

i need this information..please someone help me! What useful tool allows us to refine?

Homework Statement Estimate the average force exerted by a shot-putter on a 7.5 kg shot if the shot is moved through a distance of 3.0 m and is released with a speed of 11 m/s. Homework Equations F=ma using cos and sin? The Attempt at a Solution not sure how to begin

1. There are many different definitions of the location of the top of the atmosphere – the near edge of outer space. • Until around 1600, it was believed that the Earth’s atmosphere extended throughout space (recall that the Earth was also considered to be the center of the Universe until...

Homework Statement You measure the mass of a physics textbook to be 2.97±0.07 kg, and use this value to estimate the total mass of 800 identical physics textbooks in the bookstore. What is the absolute uncertainty in your estimate of the total mass? I have been working on this for a...

Hello everybody! I have been reading about the evolution of population growth since 1950 till now. It had many factors such as development of technology, of medecine, ... Now i want to calculate the future population growth let's say for example for 2050. In those readings i found also those...

Hello everybody! I have been reading about the evolution of population growth since 1950 till now. It had many factors such as development of technology, of medecine, ... Now i want to calculate the future population growth let's say for example for 2050. In those readings i found also those...

Homework Statement Hi, I am trying to solve this problem: I want the Big-O Estimate for this problem (n*logn + 1)^2 + (logn +1)(n^2+1)Homework Equations now only real problem comes when I try to do the square of the first term. I just don't know what (n*logn)^2 would be equal, it may be a it...

a mass of 100N has to be lifted up via string attached to pulley. What is the torque required to rotate that pulley

Following different lines of reasoning (most likely all faulty) - I can convince myself that the current estimate(s) of the Hubble age may be off by a factor or 2 (more or less) depending upon the physiology asssumed for space and the model used to describe the expansion rate - specifically: If...

1. The problem \statement, all variables and given/known data Estimate the error involved in using the first n terms for the function F(x) = \int_0^x e^{-t^2} dt Homework Equations The Attempt at a Solution I am using the Lagrange form of the remainder. I need to know the n+1 derivative of...

Around 1998 we got the estimate of 71 from Wendy Freedman's Hubble Space Telescope team. That was called the "key project" of the HST program and was one of the main reasons for HST. So much depends on it that it is important to keep trying to improve the accuracy. That 71 has stood for 10...

The problem is: Compare the performance of the forward, backward, and central difference methods for estimating the derivative of the following function: y(x)=e^-xsin(3x). Use 101 points from x = 0 to x = 4. Use a random additive error of +/- 0.01. I understand the process of solving this...

[b]1. Use Taylor's expansion about zero to find approximations as follows. You need not compute explicitly the finite sums. (a) sin(1) to within 10^-12; (b) e to within 10^-18: [b]3. I know that the taylor expansion for e is e=\sum_{n=1}^{\infty}\frac{1}x^{n}/n! and I aslo know that...

Estimate the buoyant force exerted on your body by the air ( use Pair+1.029 kg/m^3). What would be the difference between your weight in the air and your weight in a vacuum? How would I proceed with this? What Equation should I use?

Homework Statement Estimate the density of the water 5.7 km deep in the sea. (bulk modulus for water is B=2.0 x 10^9 N/m^2) By what fraction does it differ from the density at the surface? Homework Equations P=(rho)gh=F/A=B(delta l/l) The Attempt at a Solution So I have several...

How to Estimate with a Computer program a 3rd order differential equation with 4 variables and 4 equations? The equations are derived from the geodesics equation and the Schwarzschild metric. The variables are r, theta, phi and t. Any hints would be appreciated.

Homework Statement Estimate the radiation pressure due to a 100-W bulb at a distance of 5.0 cm from the center of the bulb. Assume that light is complitely absorbed. Estimate the force exerted on your fingertip if you place it at this point. Assume area of the fingertip to be 1.5 cm2...

Homework Statement Estimate the mass of a nucleus with a radius of 2.80 * 10^-15m. Homework Equations I do not know if there is an 'equation' for this. The Attempt at a Solution The answer is 2.11*10^-26.. but I don't even know how to approach this question.

Homework Statement A point charge Q is placed a distance 2R above the center of an imaginary spherical surface of radius R. Estimate the electric flux through the sphere Homework Equations The Attempt at a Solution I think the answer is 0 as Gauss law states that the net...

Homework Statement How does the speed of light's finiteness limit the size of our observable universe? Using the speed of light (c = 3 x 10^8 m/s), estimate the age of the observable Universe in years given its estimated size of about 10^26 m. Homework Equations The Attempt at a...

Homework Statement Use Newton's method to estimate the requested solution of the equation. Start with given value of x0 and give x2 as the estimated solution. Homework Equations x0 = 2 ( this is the first guess numb. you start with) the equation you use is... x = x(guuess #) -...

I'm having a problem with estimating a function using a power series... the problem is Use the power series for f(x)= (5+x)^(1/3) to estimate 5.08^(1/3) correct to four decimal places. I found all the derivatives of f(x) but I'm not sure how to make it into a power series or what form to...

HELP! (again) Homework Statement The sun sets, fully disappearing over the horizon as you lie on the beach, your eyes 20cm above the sand. you immediately jump up, your eyes now 150cm above the sand, and you can again see the top of the sun. if you count the number of seconds until the sun...

Homework Statement A clean surface of potassium in a vacuum is irradiated with light of wavelength 5.5 x10 -7 m and electrons are found just to emerge, but when light of wavelength 5.0 x 10 -7 m is incident, electrons emerge with energy 3.62 x 10-20 J. Estimate a value for Planck's constant...

The problem is this: Estimate the binding energy of the H2 molecule, assuming the two H nuclei are 0.074 nm apart and the two electrons spend 33% of their time midway between them. I assume that this problem uses the equation F=ke2/d. So far, I have that E1=F1d, and E2=F2v*t*0.33. Then...