Pulse Definition and 348 Threads

Homework Statement A string of length l = 5 m weighs M = 10 kg . A pulse wave is traveling along the string. What is the speed v of the crest of the pulse, in the uint of m/s , if the tension of the string F is 200 N ? Homework Equations v= sqrt F/u u= m/L HELP: We can...

Homework Statement A very short pulse UV laser is used to liberate a number of electrons from the negative plate in the arrangement in (i) above. The electrons drift towards the positive plate under the influence of the electric field over a time scale much longer than the laser pulse...

Hi, Energy density of the ith annular section of a Gaussian pulse is written as F(r_i, r_i+1)=2*totalEnergy/[(r_i+1^2-r_i^2)*w^2]*integral(r*exp(-r^2/w^2),from r_i to r_i+1) where r spans from r=0 to r=r_n (theoretically infinity) in n steps, w is the waist size of the beam. This...

Homework Statement A ski gondola is connected to the top of a hill by a steel cable of length 580 m and diameter 1.5 cm. As the gondola comes to the end of its run, it bumps into the terminal and sends a wave pulse along the cable. It is observed that it took 19 s for the pulse to travel the...

I`ve had a new idea in designing a pulse jet by adding a valve in it... According to my intuition and logically this increases the output many folds and I`ve given sufficient reasons for suggesting it. I have a powerpoint of my idea that I have made and I request any of you to please go through...

hello i have been having trouble working with bipolar transistor. i have been taking pulses that at less then 1us long and amplifying them with transistors. how ever if i have a bipolar transistor as part of my amplifier whether it is my inputs are as part of another stage the pulses always are...

Well I want to understand the internal working off the valveless pulse jet, I have red something but everything is qualitative, I would like to ask to you if you know some book describing every process off this kind of engines mathly, including the kadenacy effect. You have a lot of physics...

Hello, new kid on the block here. I have read the rules and hereby present my question. My aim is to calculate the period of a transient DC magnetic field from a half sine wave magnetiser output into an air core wirewound coil. Coil Resistance : 14.66 mili ohms (derived using voltage drop...

help me out with circuit diagram of pulse generator with varying pulse width,amplitude and frequency

Hi, I'm trying to build a high frequency generator. The pulse needs to have atleast 1ns rise/fall time, variable amplitude (~0-8V), 50 Ohm output impedance, and have very little jitter/be stable and I need to be able to set the pulse width and delay from ~5-1000ns. Cheers, Steve

If you were to design a pulse jet engine where would you start? How do you determine the diameter and length of the tail pipe? How do you determine the diameter and length of the combustion chamber? How do you determine the area of the air intake valve system? How do you determine...

Please suggest a method to generate a 1ns pulse. with 680MHz frequency. i.e ton: 1ns. the pin should also be able to generate pulses with pulse width anything from 1ns to 4s with 1ns step, i.e the pulse can take any value b/n 1 ns and 4s with 1ns step. This pulse is used to trigger a laser...

Does anyone know any Forumulas or how to calculate the dimensions of a pulse jet engine? I have already built several PULSE JET engines that run by scaling up an existing hobby engine to a larger size. Problem is the scaled up models run but maybe they could run better. I can not find any...

I'm new to the forum, so hello! How can i calculate the magnetic field strength of the pulse of an air core coil, the number of turns is 20 & the height of the coil is 20mm, not single or multi layered just random wound. The pulse is 10V & 1Amp, the Inductance is 200uH. Not sure how to go...

Homework Statement F(w) is the Fourier transform of f(t). Write down the equation for F(w) in terms of f(t). A rectangular pulse has height H and total length t0 in time. Show that as a function of w, the amplitude density is propertional to sinc(wt0/2). Homework Equations F(w) =...

http://i662.photobucket.com/albums/uu347/TwinGemini14/showme3.gif The top picture to the right is the picture of the rope before the wave pulse arrives, and the bottom picture to the right is a picture of the rope after the wave pulse has arrived. Notice that the rope has to stretch in...

Homework Statement Two springs are connected, one is a heavy spring and the other is a light spring. A pulse is traveling down spring A, towards a junction with spring B. Which of the following statements are correct/incorrect. A. If spring A is the heavy spring then the transmitted pulse...

I want to use a pulse current instead of continuous current in the Laser rate equation as input. What would be the equation for the Gaussian expression when I'll swap the continuous current with pulsed current in my equation and implement it in Matlab? please let me know the ans if u have any

A pulse 300ns long is made using a continuous wave laser and a very(very) fast shutter. What is (approx.) the minimum spectral width of the pulse? I have no idea where to start. For starters what is the spectral width? and how would i go about solving this problem. Not looking for a...

We have been asked to make any circuit of our choice using op-amps on a breadboard or a PCB. We have found this circuit of PULSE WIDTH MODULATOR on the net and we have decided to go for it.But our teacher wants us to explain the designing of the circuit too namely why have we used the resiistors...

I need to make a pulse of varing length. Either I need a VCR/VDR to control the length of a momo stable pules, or a VCO to trigger a preset monostable at different times. I have been trying to find some thing to do the job for me but havn't had any luck. The VCR2N/4N/7N made by Siliconix are...

A steel wire of length 5.0m and radius 0.300 mm is knotted to another steel wire of length 5.0m and radius 0.10 mm. The ires are strethed with a tension of 150 N. How long does a transverse wave pulse take to travel the distance of 10 m from the beginning of the first wire to the end of the...

Homework Statement The wave speed in a guitar string is 265 m/s. The length of the string is 63 cm. You pluck the center of the string by pulling it up and letting go. Pulses move in both directions and are reflected off the ends of the string. a) How long does it take for the pulse to...

I am new to the field of relativity. I read the Lorentz transformation between different system of coordinates. I have a question. Let's suppose that we have a Doppler shifted pulse in frequency (time dilation). This pulse has the same amplitude as the pulse seen by a moving observer. That is...

(Offtopic from another thread) So I have a super-duper laser which can emit a very short but extremely powerful pulse in some direction. This pulse is so powerful that the energy of light is say 1Kg * c**2, or the relativistic mass of light is 1Kg. What is a gravity from that light...

I am currently working a project to evaluate the power output of a single pulse through an air core transformer. Using a scope to measure the secondary output and I am confused on what voltage to use. Scope shows DC voltage, peak voltage, drop Voltage differntial of peak and drop voltage. Would...

Detailed ideas on how different wavelengths and pulse durations can limit scans

Homework Statement The figure shows two masses hanging from a steel wire. The mass of the wire is 60.0 g. A wave pulse travels along the wire from point 1 to point 2 in 24.0 ms. What is mass m? Homework Equations The Attempt at a Solution L=8.0m m_{string}=60g=0.06kg...

Homework Statement a pulse 1 m long contains 1000 α particles.at t=0,each α particles in the state ψ(x,0){1/10e^(-ik_0 ) lxl≤50cm,k_0=π/50 and 0 for elsewhere,} at t=0 ,how many particle s have momentume in the interval 0<hk<hk_0? Homework Equations introduction to quantum...

Is it possible to detonate or to ignite a fuel and air mixture using lasers, or a laser pulse, any type of laser, CO2 or other wise ? or is there any possible way of using Lasers for the propulsion of an aircraft, i am already aware of several methods, but they do not include ignite fuel, any...

Greetings I've been reading about these magnets such as these: http://www.lanl.gov/orgs/mpa/nhmfl/magnets.shtml Take a look at the pulse durations (it says in notes at the bottom "Total pulse length including decay" It's all nice but I don't understand one thing. How can they make...

I also posted this under Computer Science incorrectly... I am curious if anybody knows how to build an Electromagnetic Pulse Generator (aka EMP). I've looked for a guide online, but all of the ones I've seen are far too advanced and/or powerful for my purposes. I'm looking for about a 5'...

Hi There, A square pulse of light has the form f(x) = A exp(ik0x) for |x| < L/2 and f(x) = 0 everywhere else. I want to know how that pulse evolves overtime. I want to graph it in Mathematica. I did a Fourier transform to find the wave number spectrum, with the general form: F(k) =...

Learning about Nuclear Magnetic Resonance for a while. I have read than when the main field B0 is applied along the Z axis, it takes a time (T1) in the order of seconds for the M0 field to be created in the body we are studying. Yet we can apply a short (maybe in the order of one wave...

wat is meant by the clock pulse given to the flip flops in digital circuits. Is it just a supply that is given to the ic as long as it is held in on position. How do some chips operate when the clock goes from high to low and not when pulses go from low to high?.

Take a laser source with small bandwidth centered around the average frequency (or wavelength) With an hypothetical external modulator that can switch as fast as we want, ca we make a pulse that is spatially shorter than 1 wavelength? If not? Why? What would that entail? Clearly the number...

Homework Statement Compute the unit-pulse response h[n] for n= 0,1,2,3 for the following discrete time system: y[n+2] + 1/2y[n+1] + 1/4y[n] = x[n=1] - x[n] Homework Equations I think i am supposed to replace the functions of x with delta functions, which are zero at all except n=0...

Heres the graph... http://img205.imageshack.us/img205/4770/graphfc6.jpg" Im trying to find the Average value for a pulse waveform... the formula is Vavg = baseline + (duty cycle) (amplitude) How do I treat the amplitude since it varies...Do I treat the cuty cycle differently as...

Homework Statement I need help finding the exponential Fourier series for the pulse train below. http://img329.imageshack.us/img329/1184/20080427091409ev5.jpg Homework Equations p_T(t)=\sum_{n=-\infty}^{\infty}{D_n e^{j2nt} D_n=\frac{1}{T_0}\int_{T_0}^{}{x(t)e^{-j2nt}dt}The Attempt at a...

A current pulse exists, in which the current jumps from 0A to 10A, stays at 10A for 200 microseconds, then drops from 10A to 0A. What makes a current pulse different from the current that runs when a switch in a DC circuit is left closed for 200 microseconds...is it the same concept?

I'm trying to optimize pulse coils and determine power consumption. According to Ohm's law: P = V2/R where P=power / V=voltage / R=resistance Why isn't Ohm's law providing the same results as actual meter testing?? Testing coils with 1 "C" battery: 1.5 volts #1) 2.3 ohm coil...

I am trying to measure very high light pulses by using photodiodes. Light levels are expected to be upwards of 2-3W of irradiance. Pulse-widths are from 20uSec to 1mSec. Example light source is a highly over-driven high brightness LED, typically 200-300mW in power (during recommended current...

i'm having a LOT of trouble understanding pulse train response in RL and CR circuits... could someone please recommend a good reading over the internet... i understand LR and RC response fairly better... and use the snapshot idea to get voltage equations etc... but its very confusing and i...

Hey, I need to find a way to convert a pulse that can be in any amplitude from 0 to 5v and output DC voltage at the same amplitude. any ideas? :) Liad.

Homework Statement Multipath dispersion of a pulse of light in an optical fiber. How is this problem solved?

Homework Statement a cord of mass 0.65 Kg is stretched between two supports 28 m apart, The tension of the cord is 150 N, how long will it take a pulse to go from one end to the other? Homework Equations ok, so I really know is: speed of wave=frequency*wavelength... The Attempt at a...

How to "pulse" electric a current I'm looking for a way, or component, that will pulse an electrical current through a circuit, and I'm not sure where to start looking. I'm looking to hook a 9v battery to a small simple circuit and send the current through that circuit in pulses. For example...

Suppose I am in an inertial non-accelerated reference frame, and I observe a laser pen moving in a direction perpendicular to its length at a uniform constant velocity of one meter per second. If the laser pen were to fire very briefly, say for 1 millisecond, while in this state of uniform...

Hi there I'm looking for anyone who has the knowledge or experience that can help me develop a pulse induction gold metal detector. I have the fabrication resources but need someone who understand metal detection/circuit board technology. Please Email with experience.

Hallo to all, I have been reading a paper regarding electric pulse attenuation and the values are quoted in dB. The conversion to dB was done by multiplying the value with (20log10e) where "e" is the base of the natural logarithm. I see this conversion to dB fist time. I can not find any...