Formulas Definition and 545 Threads

A lens forms a real image of a lightbulb, but the image of the bulb on a viewing screen is blurry because the screen is slightly in front of the image plane. To focus the image, should you move the lens toward the bulb or away from the bulb. Formulas: 1/s+1/s'=1/f Well, in the book, the...

Dear All, like subsets {abc} can be found out using binary digits like 000 001 010 etc etc. how can i find the order of element for any combination which can be calulated useing following formula. n!/r!(n-r)! yours sincerley

An arithmetic progression (AP) or arithmetic sequence is a sequence of numbers such that the difference between the consecutive terms is constant. Example: 2,4,6,8,10….. Arithmetic Series : The sum of the numbers in a finite arithmetic progression is called as Arithmetic series. Example...

Hello Everyone, I have several questions regarding the deflection of a free-standing pipe wherein Force is applied on top. Appreciate any feedback that I can get. Supposing I have the following Pipe Specifications: OD: 7in ID: 6in Yield Strength: 80,000psi Modulus of Elasticity...

Im currently reading through the classic book on electrical network theory Balabanian and Bickarts electrical network theory. And I am getting confused on page 101, and the set of equations their... Eq's 67-72 dealing with accompanied sources and what exactly he's trying to imply with these...

I've never quite understood is how formula can involve division and multiplication while dealing with abstract concepts. Such as, ohm's law V = I•R where V=voltage applied I=current and R=resistance. How does that work exactly? how can you multiply two abstract concepts together to understand...

Homework Statement Potassium chromate is an important compound of chromium. It is composed of K+ and CrO42-. Write the formula of the compound. Homework Equations positive charge + negative charge = 0 The Attempt at a Solution I know how to do this problem by cross switching the...

http://photouploads.com/images/photo1igi.jpg These formulas have been provided to me for use in RC circuits. However, they haven't been defined in the lecture notes. I know Vc = voltage across the capacitor, but isn't that what Vc(t) is as well? Is there any difference between the two? Thanks

I had been looking at my Grandpa's Trike and here are some of its stats: 1 HP 24V 42.4A 3200rpm (battery 2 12V 700-800A connected in series) my concluded watts per horsepower about 1017.6 w/HP Now a different motor Tesla's Model S's motor 416HP 2 motors 85kWh battery concluded watts per...

If csc(x)=4, for 90º<x<180º sin\left(\frac{x}{2}\right)= cos\left(\frac{x}{2}\right)= tan\left(\frac{x}{2}\right)= I'm definitely stumped on this one. I know that this is the half-angle formulas. Luckily we all have sheets we can use for the exam. I know that: csc(x)=4 is the same as...

Memorization, a contemptuous, futile, and insignificant method of learning math is, I think, not the solution to my problem. Well for the arithmetical progression, I have the formula: Let: l= last term a= first term d= common difference l= a+[d(n-1)] And for the geometrical...

Hi,everyone,there is an important formula of DOS as follows, D_{n}(E)=\frac{Ω}{(2\pi)^{3}}\int_{BZ}dk\delta[E-\epsilon_{n}(k)] (1) On the other hand, another formula of DOS is often mentioned as follows, D_{n}(E)=\frac{Ω}{(2\pi)^{3}}\int_{S}\frac{dS}{\nabla_{k}E(k)} (2)...

i was having this argument with a friend that said that physics formulas are found by performing experiments and in his words "changing the variables and watching how the result changes" i found this ridiculous but i want a professional opinion (because i know that some formulas are in fact...

Homework Statement A 5kg ball (m), is to be dropped 1 meter (h) in a vacuum with no resistance in the Earth's gravity (g). Use the speed and motion equations to show that its KE at impact is equivalent to its PE at its starting point. Homework Equations PE = mgh KE= 1/2mv^2...

Hello, first post for me so I am sorry if this is in the wrong topic. I'm am from the UK studying A-Level Physics. I understand some formulas but this is testing me. Before I message my tutor I thought I would try here. Looks like a very useful website. Letters in expressions and...

These are the papers it's based off of.. http://mredwards.net/Files/Problem%20D%20Horizontal%20Projectiles.pdf http://www.mredwards.net/Files/Problem%20E%20Projectiles%20from%20an%20angle.pdf My class uses g for gravity and delta x, vx etc...

Homework Statement -∏<arg(z)<∏ (z≠0) Homework Equations arg(z) is the angle from y=0The Attempt at a Solution Arg(z) spans the entire graph since -pi to pi is the full 360 degrees so I put: -∏<arg(z)<∏ --> 0<arg(z)<2∏+k∏, (k ε Z) --> arg(z) \subset R --> arg(z) = R: all real numbers but I...

Hey guys, I was wondering if anyone can post up the formulas for integration and derivatives for everything, or if you have a link you can send me to see them. Like taking the integral or derivative of e^x I'd like to know the process for how it works.

There are two formulas for resistance R=pl/A V=IR What is the difference between them? Question b on the sheet. Why can you not use that data to calculate current flow when connected to a power source. I suspect it has something to Do with the difference between these two formulas.

Which formula's would you use to solve each set and please show the actual formulas please thank you for the help I really appreciate it as I need to know this for my final exam tomorrow, thank you! a) solving for neither set A and neither set B b) Solving for set A or Set B, but not bothc)...

I am currently reading Rautenberg's book on mathematical logic, in it he defines a propositional language ##\mathcal{F}##, set theoretically, as the smallest (i.e. the intersection) of all sets of strings ##S## built from propositional variables (##\ p_1,p_2,\ldots##) as well as any binary...

I am just finishing up my first physics course this semester (as a physics major). Although there did seem to be a lot to soak up this semester, I didn't feel like it was too bad. I am just curious though, is there a resource that has a list or other type of reference material that shows you...

I am working on virtual modeling, simulation & analysis of Heavy Trucks with Adams/truck. I need to check the Braking distance at Emergency Braking , I found some results from my simulation , Now I need the fundamentals of braking formula to know more about the theory , please help to find...

I'm very noob at this and am a bit confused: Formula 1: E_T = \gamma \cdot m c^2 Formula 2: p = \gamma m v Formula 3: E_T^2 = (pc)^2 + (mc^2)^2 Formula 3 says a particle of negligible mass can have energy, but isn't this in contradiction to formula 1? Unless maybe the velocity of the...

I have a few questions about muonic hydrogen: How to calculate the binding energy? Is there Rydberg formula analog for muonic hydrogen? Is there a way to calculate muon momentum (similar like the electron has, 2.730 e-22 kg m/s)?

I have a problem that I would like to check my work on. I am also stuck on the verifications for $E$ and $F$. Any help would be greatly appreciated. Thanks in advance. **Problem statement:** Let $G$ be the group of rotational symmetries of a cube, let $G_v, G_e, G_f$ be the stabilizers of a...

Hello, I need help to calculate the length of pipe in copper (d=22mm) to get the water in "kolam" to be 45 degree celcius and the heat pump temp is 55 degree celcius, heat pump water flow is about 1 meter cubic per hours, any simple formulas ? thank you for help

Hi, I have a question that I don't know where to start on! First, some necessary background info: $r$ denotes reflection about the $x$-axis. $t_a$ denotes translation by a vector $a$ $p_{\theta}$ denotes rotation by an angle $\theta$ about the origin Let $s$ be the rotation of the...

I was just wondering if anyone has some redox reaction formulas or corrosion formulas? Cheers Darryl

Basic Physics First post so be gentle :). I have a couple of questions :) 1) The acceleration of a body is given by a(t) = 4t3 + 3ms-2. Find its velocity and displacememt if v(1) = 0ms-1 and x(1) = 2m 2) Calculate the momentum of a mass of 10kg when its velocity is 8ms-1 3) An...

So I am new to calculus, and have been playing around with integration and differentiation. I have learned that integrating and deriving formulas, you get other formulas that can be used, like integrating surface area of a sphere to get volume. I was wondering why this is, and what limits you...

I am currently redaing Goldstein's Classical Mechanics (3rd ed. 2002, with Poole and Safko). The sections 3.10-11 deal with scattering, of the type originally studied by Rutherford, and which led him to formulate his "planetary system" atom model. Rutherford fired a beam of positively charged...

So how does one create a formula. I've seen that it starts with proportionalities and constants, but how does one connect a constant to a proportionality? Can you provide a step by step example?

I want to substitute ds by dt in the Frenet-Serret Formulas where κ is the curvature and is the torsion: Tangential:\frac{d\vec{T}}{ds} = κ*\vec{N} Normal:\frac{d\vec{N}}{ds} = -κ*\vec{T}+τ*\vec{B} Binormal:\frac{d\vec{B}}{ds} =- τ*\vec{N} I want to substitute \frac{d\vec{T}}{ds} → \frac{d}{dt}...

For a 2 Body Equation: x = - \frac{1}{2} \frac{GM}{r^2}cos(\theta) cos(\phi) t^2 +v_x t + x_0 y= - \frac{1}{2} \frac{GM}{r^2} sin(\theta) cos(\phi) t^2 +v_y t + y_0 z= - \frac{1}{2} \frac{GM}{r^2} sin(\phi) t^2 +v_z t + z_0 r= sqrt(x^2 + y^2 + z^2) \theta = atan(\frac{y}{x}) \phi =...

It seems like Zee lost a trace in his new GR text, but I am sure it is me confusing things. First, he establishes: log\: det\: M = tr\: log\: M Then, differentiating: (det\: M)^{-1} \: \partial (det\: M)=\partial (tr\: log\: M)=tr(\partial\: log\: M)=tr(M^{-1}\partial M) Then he applies...

I was fooling around with spreadsheet formulas, and created a series of rational approximations for the square root of 3: 7/4, 26/15, 97/56 etc. This is based on the continued fraction expansion for square roots. Each ratio N/D has the property that N^2 is one more than 3*(D^2)=K. I was curious...

I've always preferred to read the book in order to understood the logic and theory behind the concepts in math and physics rather than just memorizing formulas. I believe the only thing one learns by memorizing formulas is how to plug in variables and one who tries to understand the logic and...

What are the relationships between frequency, amplitude (double) and acceleration?

Much like Simpson's Rule, a.k.a. the prismoidal method, improves upon the trapezoidal method by fitting parabolic arcs across known discrete points on some function $f(x)$ rather than line segments, Newton-Cotes formulas of order 1 and 2 fit cubic and quartic curves across points on the curve...

When doing practice problems from my textbook, I often get confused with both of them. MOre specifically there are usually formulas which pertain to only one of those types of collisions. Ex: (v_1-v_2)_i = -(v_1-v_2)_f Does anyone know more of these types of formulas, or tricks to...

Will the formulas typed in latex ever be able to be viewed on the PF app? It is primarily what I use and many equations are quite difficult to read when written in raw latex. (The fact that I don't know latex probably doesn't help.) Just wondering if any mentors or really anyone for that...

Difference between 2 "Sum of n terms of geometric series" formulas Notation A) S_{n}= \sum_{k=0}^{n - 1} ar^{k} = ar^{0} + ar^{1} + ar^{2} +...+ ar^{n-1} = \frac{a(1-r^{n})}{1-r} Proof: S_{n}= ar^{0} + ar^{1} + ar^{2} +...+ ar^{n-1} - r*S_{n}= ar^{1} + ar^{2} + ar^{3} +...+ ar^{n}...

Derivatives of inverse functions--how two formulas relate? Homework Statement I know two formulas for calculating the derivative of an inverse function, both of which I know how to derive, but I don't know how to relate them to one another. Homework Equations...

Homework Statement The electric potential difference between two parallel metal plates is delta V. The plates are separated by a distance of 3 .0 mm and the electric field between the plats is E = 250 V / m. Calculate delta V Homework Equations E = - delta V / delta D The Attempt...

When using bernoullis and momentum, gauge pressure is only used in calculations, any atmospheric pressure is generally omitted, i could understand if, for example, using bernoullis, pressure 1 and pressure 2 were both atmospheric, therefore they would cancel out, but when one pressure is...

Can some one please tell me what is the difference between the two following formulas and when it is used: dQ=dU+dW dU=dQ+dW

Homework Statement Let Q(t)=t2. Find a formula for the average rate of change (ROC) of Q over the interval [1, t] and use it to estimate the instantaneous ROC at t = 1.Homework Equations For x1 ≠ x0, the average rate of change of y with respect to x over [x0, x1] is the ratio Average ROC =...

Hello, I have got these formulas used for adiabatic process. Now I would like know how the plots look like. A) y=p*V^κ , where κ is Heat capacity ratio B) y=T*V^(κ-1) C) y=T^κ*p^(1-κ) NOTE: κ (Heat capacity ratio) > 1 Thank you

I can't find a reference for what the wronskian formulas are when dealing with a 3rd order D.E. I know that: W= W[y1,y2,y3] W1= 1*W[y2,y3] W2= -1* W[y1,y3] W3= ?