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Homework Statement Hello, I'm trying to reduce the following block diagram Homework Equations The Attempt at a Solution I appear to be having some issues in doing this. The first thing that I did to reduce this block diagram was to take the forward path that has 2/(s+4) with negative...

I actually didn't know this E[F(f(t))F(g(t))] = E[F(t)F(g(t) -f(t))] = R_{FF}(g(t) - f(t))? If I were to try and find the power spectral density of X(t) I would make use of S_{XX}(f) = F[R_{XX}(\tau)]. Were F[] is the Fourier Transform. S_{XX}(f) = F[2*delta(\tau) - delta(\tau - 1) -...

Hey MathematicalPhysicist, Thanks for the reply. I didn't realize this was so simple. My new attempt at a solution I know that . But I don't understand how this equation is true . It reminds of the simple fact that if LHS = RHS LHS + 1 = RHS +1 But that doesn't seem to be the case here...

sorry I didn't mean to post

Homework Statement I'm posting this question here at this point. I am having difficulty understanding autocorrelation in terms of solving the problem below. I don't seem to understand the math behind this. A white noise process W(t) with unity (N_0/2 = 1) power spectral density is input to a...

The value for I_x doesn't seem to be correct. I'm not exactly sure how you got the value that you did. The node to the left of the 5 ohm resistor there's only three paths for current to flow through. It looks like your summing the currents at node A when you solve for Ix? If this is the case...

Oh ok let me look through this again.

What about the voltage across the inductor?

When you did your conversion, point B shouldn't be connected to ground, it wasn't in the original problem before the conversion.

I would recommend not memorizing such equations. It really makes things complicated when presented with problems that don't fit them. There are several ways you could solve the problem. Do you know the equation for KVL for after the switch is opened?

Homework Statement A white noise process W(t) with unity (N_0/2 = 1) power spectral density is input to a linear system. The output of the linear system is X(t), where X(t) = W(t) - W(t - 1) Determine the autocorrelation of X(t) and sketch it. Homework Equations Let τ denote a time...

Hi, I'm an undergraduate EE major and am having trouble understanding IGBT. I understand the basic principle, a PNP transistor in ? (forgot the name) configuration with a MOSFET with a parasitic NPN transistor. I understand that it's a 4 layered device. I however think I would struggle trying...

My text says that we can find the frequency, ω_{max} at which the maximum phase angle, Θ_{max}, occurs ω_{max} = \frac{1}{T\sqrt{β}} But this doesn't really seem to help since I don't know the frequency ω_{max}, unless it's the bandwidth frequency ω_{BW}, which I don't think it is. My text...

For a lead network G_{c}(s) = \frac{1}{β}\frac{s + \frac{1}{T}}{s + \frac{1}{βT}} I'm still unsure where \frac{1}{\sqrt{2}} came from though. There's a standard representation for the compensator C(s)? Edit 1: From the characteristic equation 1 + kG(s)C(s) = 0 kG(s)C(s) = -1 kG(s) = -...

done editing Homework Statement I'm given the following transfer function that represents a physical apparatus G(s) = \frac{X(s)}{F(s)} = \frac{3.333*10^{4}}{s^{2}} I'm asked to design a lead compensator to achieve closed-loop stability. The requirements are that it must have a transient...

Thanks for your response. Should this go in the advanced physics forum? This question is actually from a control systems class, but I posted it in the physics forums because I'm having a hard time understanding the physics behind this problem, especially the free body diagram. I was able to...

Homework Statement I'm given the following diagram And asked to find the transfer function G(s) = \frac{X(s)}{T(s)} and seem to be having some difficulty doing so. Homework Equations The Attempt at a Solution Apparently this is free body diagram I seem to be having difficulty...

Homework Statement Given a electrical circuit as one below One can find the transfer function For second order systems this can be written as I know that the damping coefficient can be found using the following formula In the over damped case ζ>1 can easily occur depending on the...

Hi, I seem to be having some issues going from state space representation of a system to signal flow graph representation. My troubles seem to be, if I have something like this \frac{d}{dt}x_{1}(t) = v_{1}(t) In state space representation I list functions to which the derivatives are as...

Homework Statement I'm trying to implement the function F = A'BC+ABD+AB'D' using 3 tri-state buffers. Apparently I'm supposed to connect the buffers together and use C, D, and D' as inputs to buffers. I'm supposed to pass A and B through logic to get the input signals. I'm supposed to...

Well you've stumped me to stay the least, and I'm a bit concerned by suggesting that the problem can't be solved I did not realize that I could think of the transistor and the diode as a switch. This may lead me in the right direction. I'm not exactly sure why it could be considered a switch...

Homework Statement I'm given the following circuit http://imageshack.com/a/img850/8576/b3ny.png [Broken] and given L, V_{in}, D, P_{o}, f_{s} and q(t). How do I go about finding T_{s}, V_{a}, i_{L}, i_{L} ripple, and I_{o}. Homework Equations The Attempt at a Solution I'm honestly not...

So if I wanted positive Vload/Idist it would just be the opposite magnitude, -1/(CFS)?

Homework Statement Hi, I was wondering if someone could help me create a basic differential equation in Simulink. I'm trying to create the following equations http://imageshack.com/a/img197/1379/cic.PNG [Broken] I tried using this as an example...

So if you have no idea what one of the functions in the frequency domain is and you get something like inverse Laplace transform( F(s)G(s) ) and you know what G(s) of is but F(s) is not given then you have no way to evaluate the expression?

Hi, Does anyone know a program that I can put on my TI-84 calculator that will allow me to input any transfer function and get the state space representation of the system or the other way around. For example G(s) = \frac{\sum(K_{i}s^{i})}{\sum(P_{i}s^{i})} The calculator prompts you...

Is it really just -\frac{C_{f}s}{1 - C_{f}s}?

Homework Statement I'm trying to find \frac{V_{Load}(s)}{I_{Dist}(s)} using Mason's rule. I was able to solve for \frac{V_{Load}}{I_{Cf}(S)} using Mason's rule but am not sure how to solve for \frac{V_{Load}(s)}{I_{Dist}(s)}. http://imageshack.com/a/img31/4299/zr5.PNG [Broken] Homework...

Homework Statement Is there a way to evaluate L^{-1}(\frac{F(s)}{s + a})? I'm sure if it can be evaluate. Homework Equations The Attempt at a Solution

Homework Statement http://imagizer.imageshack.us/v2/800x600q90/690/0tab.png [Broken] [Broken] I'm asked to find the transfer function and then find the state space representation and seem to be stuck. Homework Equations The Attempt at a Solution My textbook states that for a...

Homework Statement \dot{} I'm given the following circuit http://imagizer.imageshack.us/v2/800x600q90/43/bwka.png [Broken] Homework Equations The Attempt at a Solution I come up with the transfer function to be G(s) = \frac{s}{2+\frac{1}{s}}. The question asks me to...

How would you recommend solving this problem then, if there's a much easier way to solve this than I would like to know how that can be done. Resolving that into partial fractions is very difficult to do.

Thanks, I was able to figure it out

So this problem becomes L(t*u(t) - t*u(t-T)) = \frac{1}{s^{2}} - L(t*u(t-T)) = \frac{1}{s^{2}} - \int^{∞}_{0^{-1}}e^{-st}t*u(t-T)dt = \frac{1}{s^{2}} - \int^{∞}_{0^{-}}e^{-st}tdt Now I do u substitution to evaluate the integral. u(t) =t, \frac{du}{dt} = 1. \int dv = \int e^{-st}dt =...

Homework Statement Given \frac{dx}{dt} + ax = Asin(ωt), x(0) = b Solve for x(t) Homework Equations The Attempt at a Solution I take the Laplace transform of both sides and get sX(s) - x(0) + aX(s) = \frac{Aω}{s^{2} + ω^{2}} X(s) = \frac{b}{s + a} + \frac{Aω}{(s^{2} + ω^{2})(s+1)} The...

Homework Statement Find the Laplace transform of f(t) = t \forall 0≤t≤T, 0 otherwise Homework Equations The Attempt at a Solution I write the function as tu(t)-t*u(t-T) That is turn on the function t at t=0 and turn the function t off at t=T. It seems to be right to me...

Homework Statement Find the transfer function, G(s) = \frac{V_{0}(s)}{V_{i}(s)} for each network shown in figure P2.3. [Section 2.4] http://imagizer.imageshack.us/v2/800x600q90/20/1ocq.png [Broken] Homework Equations The Attempt at a Solution When I try and solve this problem...

Thanks for all of the help guys. It make since to me now. I clicked on all of the links, but was shocked by the link in #6 that went to a AP Physics B class website. I took that class four years ago and learned this material then, apparently I have forgotten all about it in such a small amount...

This is interesting no one has ever explained this to me. How do I know when they invert and how do I know when they don't? Δ = Δ_{p} + Δ_{r} The inverted wave travels 2t as far since it travels through the thickness twice, so then why do we use 2nt as apposed to just 2t for thin film...

My book doesn't mention this until Michelson interferometer. It doesn't explain why your supposed to use lambda/2. It appeared in my lecture in thin film interference. I can't seem to find though any explanation as to where it comes from. I also have searched the internet for some sort of...

Homework Statement Plan plates of glass are in contact along one side and held apart by a wire 0.05 mm in diameter, parallel to the edge in contact and 20 cm distant. Using filtered green mercury light (λ = 546 nm), directed normally on the air film between plates, interference fringes are...

Wait hold on. What allows us to simply replace the wavelengths with the frequencies and just interchange them? I thought that the equation applied to wavelengths. Oh ok I know why lol.

Ya. I just read underneath that part and it says that when v << c Eq. (4-44) (the equation I posted in the first post for the Doppler Effect) is approximated by \frac{λ^{'}}{λ} = 1 - \frac{v}{c} Which I didn't realize. I remember reading it earlier but it left my mind because I would...

Homework Statement A laser emits a monchromic beam of wavelength λ, which is reflected normally from a plane mirror, receding at a speed v. What is the beat frequency between the incident and reflected light? Homework Equations The Attempt at a Solution The solutions starts off...

I have just read the caption of the figure and now realize that v_{p}≈\frac{E_{3} - E_{0}}{h}. The only problem now is that I don't know E_{3} or E_{0}. Looks like I might be able to solve this. I was able to solve the problem. My only concern is that I didn't use the given wavelengths in the...

I'm not sure if this question should be posted in the introductory physics section or the advanced physics section. Consider an amplifying medium, composed of homogeneous broadening four-level atoms as show in figure 26.5, page 557 of textbook. http://img689.imageshack.us/img689/6108/lt2f.png...

Oh wow. I can't believe I didn't see that thanks.

Homework Statement Consider a situation in which a wave is traveling in the negative x-direction encounters a barrier and is reflected. Assume an ideal situation in which none of the energy is lost on reflection nor absorbed by the transmitting medium. This permits us to write both waves with...

never mind

Homework Statement The dispersive power of glass is defined as the ratio \frac{n_{F} - n_{C}}{n_{D} - 1}, where C, D, and F refer to the Fraunhofer wavelengths, λ_{C} = 6563 \stackrel{o}{A}, λ_{D} = 5890 \stackrel{o}{A}, and λ_{F} = 4861 \stackrel{o}{A}. Find the approximate group velocity...