Formula Definition and 1000 Threads

Please explain in detail how to derive formula for capacitance of spherical capacitor?

This is basic maths but I kind of forgot how to retrace such an equation. My question is: why does "+-2*xi(n-1)*delta" which is in the middle of the first long equation cancle out? I'm thankful for an answer!

dear sir, i wish to know if i am correct. a^2+c can be a prime number provided if a is even then c is odd or vice versa, also a and c are not multiple of same number. and c is not a negative square of any number. finally prime number is unique combination of 1,2,and other powers of 2. each power...

Hello everyone, I have a question regarding a formula which can be derived from conservation of momentum and energy in the Compton effect. From conservation of momentum and energy during the collision of a photon with an electron, it is possible to get two expressions for the final energy E of...

Homework Statement Hello! Please, help me to get through equations. I can't derive the equation in the way suggested. Here is the definition: So, if vertex is at (h, k) and there is a given point on a parabola at (x; y), then focus is at (h; k + p), and point of a directrix is at (x; k -...

Homework Statement Laser light with a wavelength 633 nm is used to illuminate two slits separated by 0.125 mm. The width of each slit is 0.0150 mm. Assuming that only fringes between the first minima in the pattern are counted, how many bright fringes are visible? lambda = 633nm d = 0.125mm w=...

Hello. I asked my professor and he couldn't figure it out. If train A and B leave the same point at the same time, A traveling 60mph, B traveling 75mph, how long will it take for B to have traveled twice as far as A?

Hello everybody! I'm sorry if it's not the right section to post in. I'm trying to solve this exercise: $$\frac{1}{2i\pi}*\int_{8-i\infty}^{8+i\infty}\frac{e^{s(t-5)}}{(s+4)^2}ds$$ The request is to find the result in function of $$t$$ I know i must use the Riemann inversion formula, and so the...

The eccentric mathematician Paul Erdos believed in a deity known as the SF (supreme fascist). He believed the SF teased him by hiding his glasses, hiding his Hungarian passport and keeping mathematical truths from him. He also believed that the SF has a book that consists of all the most...

A sample of sulfur having a mass of 1.28 g combines with oxygen to form a compound with a mass of 3.2g. What is the empirical formula. So what i did is found the mass of oxygen which is 1.92g . Then converted the 1.28g S to 0.04 mol. Then converted the 1.92g O2 (as it says oxygen, or should it...

I'm having a physics lab in which a report needs to be submitted after an experiment. The experiment includes many measurements: values with their errors. I need to round the error up to 2 significant digits, and then to round the value up to to the amount of digits that the error is presented...

They ask for both $ \sum_{n=0}^{\infty} p^n Cos nx, also \: p^n Sin (nx) $ I'm thinking De Moivre so $$\sum_{n=0}^{\infty}p^n (e^{ix})^n = \sum_{n=0}^{\infty} p^n(Cos x + i Sin x)^n= \sum_{n=0}^{\infty} (pCos x + ip Sin x)^n$$ I also tried a geometric series with a=1, $r=pe^{ix}$ But...

Homework Statement Show that phi_n will find the proper phi_4. IE: show that it gives the correct normalization constant. Richard Liboff...chapter 7 Homework Equations A_n = (2^n * n! * pi^1/2)^-1/2 The Attempt at a Solution I don't know where to start really. I tried some things with <...

I am hung up on what must be a very elementary matter, but I’m unable to see where I’m wrong. I reference R. Shankar's "Principles of Quantum Mechanics". For the free particle with https://www.physicsforums.com/file:///C:/Users/DANIEL~1.ABR/AppData/Local/Temp/msohtmlclip1/01/clip_image002.png ...

So I'm supposed to find the exact values of the sine, cosine, and tangent of an angle by using a sum or difference formula ( i.e. sin(x+y)=sin(x)cos(y)+cos(x)sin(y) ), but this is the angle I was given: ${-13\pi}/{12}$. How do I use a sum or difference formula to get the sin, cos, and tan of that?

Homework Statement what is y ′and y bar ? why y ′ is changed to y bar ? why are they = 0 ? Homework EquationsThe Attempt at a Solution

Homework Statement An ideal solenoid is expected to generate a dipole field that falls off quickly as you move away from the solenoid. The magnetic field at distance r along the axis of the solenoid is given by B = (Mo/ 2pie) (M/r^3) In this equation the parameter M is called the dipole moment...

In physics lab course I measured equivalence conductivity of NaCl in infinite dilution Λ0 as a function of temperature T. So I have observations (T, Λ0) and fitted a line using the least squares method in Ms excel (lol :oldbiggrin:). The formula of the line is Λ0(T)=c0+c1T, where c0 and c1 are...

Sorry, there's going to be a lot of preamble here. I've written a book that involves a lot of space travel, therefore a lot of time dilation (all sub-light travel). I've been calculating the transit times and subjective durations by brute force, i.e. I wrote a program to calculate tau on a...

Imagine the flagpole and ball with mass m fall together. Can I here use the formula mg*l*sin(theta)=(1/2)*mv^2 If I can, in what direction will the velocity vector be - is it going to be tangential to the flagpole?

Question number 1; find the angular speed. I imagine a point mass at the very top, it has potential energy mgL, this is converted to kinetic energy 1/2*mv^2. I put them equal to each other and say that v=ωL. This gives me ω=sqrt(2g/L), the answer is supposed to be ω=sqrt(3g/L). Why can't I...

Hi, I was looking for a formula to describe capillary action speed in a medium. On wikipedia (https://en.wikipedia.org/wiki/Capillary_action) I came across a formula which describes the cumulative volume of a liquid drawn by capillary action after time t where V is cumulative volume, A is...

hi all... i have payment schedule with parameter like this : e.g. original price $\$$5000 - if i pay in <=6 months i have penalty (add penalty) 1% from original price - if i pay in >6 months i have penalty (add penalty) 10% from original price e.g. my problem is : i have $\$$5000 and...

Homework Statement I need to transpose the following equation to make E the subject (see deflection due to bending attachment .jpg) and I'm not sure whether my attempt is correct or not. Could anybody advise on the corrections needed on my attempts. Homework Equations see deflection due to...

Homework Statement To calculate the moment of inertia of a cantilevered tapered tube with mid-thickness large radius RL and mid-thickness small radius RS Homework Equations The Attempt at a Solution Area of the larger end of the tube AL=2*pi*RL*t Area of the smaller end of the tube...

Homework Statement The electric potential on the surface of a sphere of radius R and charge ##3##×##10^-6## is 500V.The intensity of electric field on the surface of the sphere (in N/C)is Homework Equations ##V##=##(\frac{1}{4πε0}\frac{q}{R})^2## The Attempt at a Solution Actually I have...

I was browsing about my optics books,completing numericals and stuff When I found a a statement called different lens formulas It had 2 formulas One,called the thin lens formula or rather the geometric sign convention formula was called 1/v-1/u=1/f(Symbols have their usual meanings) and another...

Pentago is a board game and you can think of it as a highly advanced version of tic-tac-toe. With the aid of supercomputers, it has been strongly solved. Just like tic-tac-toe, it is possible for the player who starts first to always in. I'm looking for a formula to always win at Pentago if...

Give an example of a formula for a vector field whose graph would closely resemble the one shown. The box for this figure is [−2, 2] x [−2, 2]. Not sure where to start.

Hello! If T denotes running time, then, as I heard at the lecture, T(n/2) + T(n/2) + O(n) = O(nlogn) where T(n/2) running time for sorting the left half T(n/2) running time for sorting the right half O(n) merging sorted Please, help me to see the math - how did the...

well ... we are studying bethe and weiszacker semi empiric formula , and i am confused . specifically about the third term the asymmetry term and how it lowers the binding energy . so just so i know that i am getting this straight , originally the binding energy no matter the nucleus is...

In my formula sheet I have written down that deltaPEg = (PEg final - PEg initial) but then I have written down that -(deltaPEg) = (PEg final - PEg initial) which one is right? Oh and another question, when do I use the formula deltaK + deltaPE = 0?

How would one prove quantum gravity, would there be some thing observable or would it just be a mathematical formula.

Why do we multiply permittivity of vacuum with relative permittivity? What does this calculation mean?

why is the formula of energy in a capacitor E= C x U^2 /2 I understand it mathematically, but I do not understand it if you apply it to a real situation. Is there anyone who can explain that?

If x values are: 10, 20, 30, 40, 50 corresponding y values are:20, 65, 180, 390, 505 then what is y value at x=25. I was having an argument with maths sir. I was saying to take x0 as 10 to get the answer as 107.14, which is correct application of formula, but our maths sir said that we should...

Homework Statement At 9 P.M. an oil tanker traveling west in the ocean at 18 kilometers per hour passes the same spot as a luxury liner that arrived at the same spot at 8 P.M. while traveling north at 23 kilometers per hour. If the "spot" is represented by the origin, find the location of the...

A question like : A very thin layer of oil is on the surface of a puddle of water. If the layer of oil is 400 nm thick, what frequency of light in the visible part of the spectrum will most strongly be reflected? Given the index of refraction of oil is 1.4. Can we think of the layer as a single...

Homework Statement how to divide moment of inertia of solid sphere about its central axis?. Solid sphere has radius R, mass M. Homework Equations I=∫r2dm 2/5 MR^2 The Attempt at a Solution https://photos.google.com/search/_tra_/photo/AF1QipPoXyad0q1Y3yisc0LeeJHGApkIrGbitK6kAk5p i try to...

Write a differential formula that estimates the change in the volume $V=\frac{4}{3}\pi{r}^{3}$ of a sphere when the radius changes from $r_0$ to $r_0+dr$ $$dV=4\pi{r}_{0}^{2}dr$$ this was one of the selections but I didn't know how to account for the $r_0$ to $r_0+dr$

I am looking for a program ( off-line) that makes me write math formula and equation in a standard LaTeX form. I am not familar with LaTeX but I can learn the codes fast. I also need the created formula to be transformed into Ms-Office as I am not happy with MS-math editor.

using Newtons equation for gravitational force one can fling that the acceleration due to gravity, g' above the surface of Earth as g' = g (d/(d+h)) but I find that there is a different equation for the same as g' = g ( 1- 2h/r ) I know the first formula is right but I can't doubt the...

Pws=1000⋅e[[52.58]-[6790.5/T]-[5.028lnT]] T= temprerature in Kelvin Pws= Saturation vapour pressure I plugged in my temperature to the formula in Kelvin, I couldn't arrive at the correct answer. How do you get the e value of the equation (superscript above). My problem could be the trigonometry...

Need formula to calc. lateral and/or eccentric loads on trailer hitch ball when moving down the road hauling a trailer with gross trailer weight (GTW) of 10000 lbs, Tongue weight (TW) of 1200 lbs.

I have figured out a formula that generates prime numbers along with the proof that all such generated numbers are primes. The way it works is that you have to input consecutive prime numbers staring from 2 and ending at some Pn. And no it's not primorial minus or plus 1. Is this of any value...

Hi this is my first post ever in MHB, and I'm in Calculus 1 wondering which formula to use to find derivatives. There are 2 as far as I know: (1) and the one one at the beginning of this: (2) Example Problem: How would i know which formula to use? Is there a particular reason the...

Homework Statement [/B] Don't know if this goes here or in the advanced bit, thought I'd try here first! I know the general solution of a 1D wave equation is given by d'Alembert's formula ##u(x,t) = 0.5[u(x+vt,0) + u(x-vt,0)] + \frac{1}{2v} \int_{x-vt}^{x+vt} \frac{\partial u}{\partial...

I have a long-standing puzzle about the Kubo formula of thermopower S=L_{21}/L_{11}. The electric conductivity (L_{11}) can be expressed in terms of real time current-current correlations. Similarly, the heat conductivity can be expressed in terms of real time correlations of heat currents...

Hello, I found a Math formula, not long time ago, I went to a journal centre, there I was told that I need to check if my formula is new, or was already discovered, they said that it's not their job to check that. So, what I'm supposes to do? Also, is there a website/map that can show all my...

Homework Statement I need to proof that Rodrigues’ formula satisfies Laguerre differential equation Homework Equations Rodrigues’ formula of Laguerre Laguerre differential equation The Attempt at a Solution first,I have to calculate = I tried to sum both terms and this is what I got...