Derive Definition and 620 Threads

Behaviour of any first-order circuit can be described by a first-order ordinary differential equation (often called the state equation) of the form : dx/dt + αx = βy(t); x(0) = x0 where x is the state variable (usually the voltage across a capacitor or the current across an inductor), y(t) is...

1. Derive Wien's displacement law from the Planck Spectrum. 2. Planck's Law: \frac{2hv3}{c2(e\frac{hv}{kt}-1)} Where v = frequency; c = speed of light; h = Plank's constant k = Boltzmann's constant The Attempt at a Solution Well, the first thing I wanted to confirm was that this was in fact...

Hi, dear all, hope your guys allow me to ask this tricky question. Refer to the attachment, i would like to derive the principal radii of an ellipse, the final equation and figure is provided in Stephen Timoshenko Theory of plates and shells 2nd edition. consider the ellipse has form...

Homework Statement Derive the expression v = lnfn where ln is the shortest distance between nodes for the nth harmonic. Homework Equations v = wave speed ln = shortest distance between nodes for the nthharmonic fn = frequency of the nth harmonic The Attempt at a Solution Is it...

So i am having a slight problem deriving this equation. there is a simple way which is v=u+at -> t = v-u/a s = (v+u)t/2 so s = (v+u)*(v-u)/2a 2as = (v+u)(v-u) 2as = v2-u2 v2=u2+2as but i am having trouble understanding this way V2=(u+at)2 V2=(u+at)(u+at) V2=u2+a2t2+2uat - i can't...

"why does the professor derive the equation?" I often hear people of other majors (engineering) ask me why the professor derives the equation to be used in some situation (like a continuous charge distribution electric field from coulomb's law divided by the test charge) instead of just giving...

I have a function, x(t), where x and t are real scalars. I have been trying to derive an analytical expression for the nth derivative of x with respect to t:x^{(n)}(t) \triangleq \frac{d^n}{dt^n}x(t)= \ \ ?However, getting a general expression is proving tricky. Meanwhile, I have managed to...

I am aware that physicists are trying to derive born rule from unitary evolution. Has there been any success? What is the current status of that program?

Homework Statement I should derive \vec{F_{q}} = \frac{-q'^{2}}{4∏ \epsilon_{0}} \frac{r'/a}{(r'^{2} - a^{2})} \hat{r} from \vec{F_{q''q'}} = k\frac{q' q''}{\left|\vec{x'} - \vec{x''}\right|^{2}} Homework Equations The Attempt at a Solution I know that q'' = -q'...

1. (x=X1+vt1, x1=x-vt ) 2.(t=t1+vx1/c2, t1=t-vx/c2 ) I know that 1. is x in terms x1 and x1 in terms of x. I understand it very well, the adding and substracting of velocity. But i am unable to understand the 2.how these equation are derived and what does they mean. The mane...

I am a third year undergrad in the UK and I have been looking over my first year notes on special relativity. I found this passage talking about predictions we can derive if light is corpuscular. "If light is corpuscular (emitted like bullets) one expects the speed of light to depend on the...

Homework Statement A subway train travels over a distance s in t seconds. it starts from rest and ends at rest. In the first part of its journey it moves with constant acceleration f and in the second part with constant deceleration r \, . Show that s \, = \, \frac {[\frac {fr} {f \...

Homework Statement Hey, For an assignment I need to derive the optimal angle for maximum range (derive Equation 2 below). I know how to derive equation 1 but I need to derive the second equation so I can substitute h = 0, and h = 1, into it, to show the optimal angle for maximum range for...

Homework Statement There is a fixed spherical body of mass M whose center is to be taken as origin. Another body of mass m whose initial position vector \vec{r} is given. This body is projected with initial velocity \vec{v}. Find the equation of trajectory of body with mass m around the body...

Homework Statement I have this statement: If M(x,y)dx+N(x,y)dy=0 is a homogeneous DE, then μ(x,y)=\frac{1}{xM+yN} is its integrating factor. The problem is, how do we derive this integrating factor? Homework Equations For homogeneous DE, we have f(kx,ky)=k^n*f(x,y) We also have...

Where How did he come up with that?

Homework Statement Derive a relationship between the speed v, of a body moving in a circle of radius r, and the frequency f, of the revolutions. Homework Equations v=2πr/T T=1/F The Attempt at a Solution Well, I thought this would be as simple as solving for F in the second...

Homework Statement A circular conducting loop with radius a and resistance R2 is concentric with a circular conducting loop with radius b much greater than a and resistance R1. A Resistance dependent voltage is applied to the larger loop, having a slow sinusoidal variation in time given by...

Derive for time! D=Vit+1/2at^2 THANKS for you help

Derive "Focusing Theorem" in Gravitation by MTW I followed the logic in Chapter 22.5 from Misner&Thorne&Wheeler, trying to derive the focusing theorem, i.e. equation(22.37). The problem that blocks me is the derivation of (22.36) for the cross section area. I already find the equation for...

Homework Statement A composite material is made from a matrix with a tensile modulus of 5 GPa and two different continuous fibres with moduli of 360 GPa (type !) and 450 GPa (type B) respectively. a) Derive expressions for the transverse modulus and the longitudinal modulus of a...

Hello, I'm looking at some sporting data (similar to goals in a match) and trying to figure out what distribution applies to their count per match. Typically, Poisson is used in the industry to model the distribution. When I look at the historical events, poisson isn't too bad, but tends...

How do you derive the results, a=dv/da

Homework Statement Derive the following formula using Taylor series and then establish the error terms for each. Homework Equations f ' (x) ≈ (1/2*h) [4*f(x + h) - 3*f(x) - f(x+2h)] The Attempt at a Solution I honestly have no idea how to go about deriving this. The professor did...

Let Y ~ Bi(m,q). Use the definition of E[g(Y)] to derive E[Y^2]. Hint: Write Y^2 as Y(Y-1) + Y. You do not have to re-derive E[Y]. Not sure where to start with this; my initial reaction was to use the moment generating function?

Hey all, I've been trying for a while now to derive the following solution, for a circular cylinder under uniform flow: φ(r,θ)=U(r+\frac{R^2}{r})cos θ where φ is the flow potential that satisfies Laplace's equation, as defined in this article...

Hi I am measuring the acceleration of an oscillating body with a triaxial accelerometer. I want to derive some kind of vector average of the 3 channel output. Someone suggested using x= √(a squared + b squared + c squared) ... where x is the vector average and a, b and c are the...

I'm tired of having to look up the kinematic equations every time I need to use them (I tutor lower devision students a lot). Is there an intuitive and memorable way to derive them? As in, it's easy to derive x=x0+v0t+at2 just by integrating a constant force. Can I get the others without...

Homework Statement Derive an expression for the rate of interactions in a fixed target experiment, for which the beam of incoming protons has a current I, the target density is ρ(g/cm^{3}), the target thickness is d and the interaction cross-section is σ. You assume that the beam particles...

i have a coax cable that will be used in data transmission. i have measured the open and short impedance and then characteristic impedance(Zo) for the cable. Eventually I will have a transmitter with Z_source in one end of the cable and receiver with Z_load at the other end of the cable. Is it...

In my career, so far, the first two pages of the attached sheets contains everything I've ever needed to have in my head; the last sheet contains most things I've had to derive. I hope you find this helpful. https://www.physicsforums.com/attachments/910._xfImport Comments and questions should...

I'm not understanding how the equation of the electric field due to an electric dipole is derived. This is how my book derives it: Say you have electric dipole composed of charges +q and -q a distance d apart, with the negative charge at the origin of the z-axis. Then, at any point z, the E...

I guess it was Whitehead and Russell who tried to prove that all of math could be derived from the principles of basic logic. Where is that effort today? I'd rather not read a 3 volume set to understand how 1+1=2 can be derived from logic. Is there a more modern text on the subect? Is it still...

Homework Statement Three charges with values + 20 μC, -10 μC and -10 μC are placed at the corners of a 0.10m square, as shown. c) Consider a sphere of radius 0.3m which totally encloses all three charges. Using Gauss's law derive an expression for the flux through this surface. Homework...

Homework Statement There are other ways to derive the kinetic motion equation. show an alternative way using the equations of motion Homework Equations Ek= 1/2mv^2 The Attempt at a Solution W= FD W= MAD = m( v2-v1/t)(V1+V2/2) T = M/2 ( V2^2-V1^2) = EK= MV^2/2 they...

Homework Statement http://a1201.hizliresim.com/t/f/1sjw1.gif http://a1201.hizliresim.com/t/f/1sjxk.gif Homework Equationshttp://d1201.hizliresim.com/t/f/1sjxx.gif The Attempt at a Solution http://c1201.hizliresim.com/t/f/1sk69.gif I think there will be a mistake at solution and I can't...

I start with the expression for kinetic energy \Large E = \frac{1}{2}mv^2 Differentiate both sides by x \Large \frac{dE}{dx} = m v \frac{dv}{dx} Substitute the following expression for the velocity v \Large v = \frac{dx}{dt} To get \Large \frac{dE}{dx} = m \frac{dv}{dx}...

Hello. I am in the middle of a paper on Hubble's law and the Friedman equations, I would like to show that with modern measurements of redshift (or λ') and distance, one can use these to find a modern value of Hubble's constant. I however need some data to do this, so does anybody know of a...

Hello. first, sorry for my poor English. Derive characteristic wavelength from radiation powerThis is radiated power from bending magnet (synchrotron storage ring accelerating electron to get x-ray) and these are wave distribution from storage ring and what I have to derive is as follows...

Hello! Can anyone help me / tell me how to derive at Leibniz's notation? As in how was the formula derived?

The question asks the student to use Taylor's formula to calculate the exact values of higher derivatives f '[0], f '' [0], f ''' [0], ... , f^6'[0] of the function f[x] defined by the power series x/2 + x^2/12 + x^3/240 +x^4/10080 + ... +((k x^k)/(2 k)!) + ... My first...

From my understanding the job of a theoretical physicist is to derive theories to explain phenomena in nature. But let's say you aren't the best problem solver in the world. You are good enough in your physics class to get the 3.5 GPA but you are never able to solve those extra credit problems...

how to get this equation: Vout/Vin = [RL]/[-[ω][/2]+jω(R/L)+1/(LC)]

Do I take the derivative of the density fct and set it equal to 0, then solve for t?

Homework Statement I came across an expression in the following pdf at the bottom of page two: http://iweb.tntech.edu/murdock/books/v4chap2.pdf Homework Equations The electric field for a disk: \vec{E} = \frac{\sigma}{2{\epsilon}_{0}} ( 1 - \frac{z}{\sqrt{{z}^{2} + {r}^{2}}}) Now logically...

I want to derive some physics equations from other equations. a) How can I derive this formula: R=Vo^2(sin(sα) / -a from these two equations: (1) x=(Vo cosα)t (2) y=(Vo sinα)t + 1/2at^2 Things I know - I think the way to do this is to isolate the variable t in equation (1) and...

I'm struggling to derive some thermodynamic equations from this http://my.safaribooksonline.com/book/chemical-engineering/9780132441902/thermodynamic-properties-from-volumetric-data/ch03lev1sec1" : Homework Statement I'm trying to derive all the equations from 3.8 to 3.14 for Pressure...

Is it? If so, can you show how? Thanks :smile:

Homework Statement Measuring the flux of a star as a function of the time, the flux exhibit a decrease of 1.65% for 2h 56m, periodically every 57.22 days. Such decrease is ascribed to a planet transit. The continuous spectrum of the star is like a black body with T= 9500 K, and its...

Homework Statement I need to derive an error equation using back substitution for the angle to radian equation Homework Equations θ^rad = θ° * 2pi^rad/360° The Attempt at a Solution How can I back substitute, is everything after the θ° not all constants??