In electronics, acoustics, and related fields, the waveform of a signal is the shape of its graph as a function of time, independent of its time and magnitude scales and of any displacement in time.In electronics, the term is usually applied to periodically varying voltages, currents, or electromagnetic fields. In acoustics, it is usually applied to steady periodic sounds—variations of pressure in air or other media. In these cases, the waveform is an attribute that is independent of the frequency, amplitude, or phase shift of the signal. The term can also be used for non-periodic signals, like chirps and pulses.
The waveform of an electrical signal can be visualized in an oscilloscope or any other device that can capture and plot its value at various times, with a suitable scales in the time and value axes. The electrocardiograph is a medical device to record the waveform of the electric signals that are associated with the beating of the heart; that waveform has important diagnostic value. Waveform generators, that can output a periodic voltage or current with one of several waveforms, are a common tool in electronics laboratories and workshops.
The waveform of a steady periodic sound affects its timbre. Synthesizers and modern keyboards can generate sounds with many complicated waveforms.
From a textbook - The reason why the polarization plays a key role in the description of nonlinear optical phenomena is that a time-varying polarization can act as the source of new components of the electromagnetic field... the wave equation in nonlinear optical media often has the form...
Homework Statement
Given the first cycle of a waveform:
f(t)=2u(t)-2u(t-1)+u(t-2)-u(t-3)
-- Plot the first cycle of the wave form
-- Find the Fourier Coefficients
Homework Equations
Given above
The Attempt at a Solution
No idea yet. Will appreciate any help.
given the below graph of the waveform, what is the rootmeansquare voltage.
[PLAIN]http://img41.imageshack.us/img41/5296/voltage.png
Please help, i have no idea how to do this. Note that the waveform repeats itself every 3 seconds. thank you
Greetings Physics Forums! This is my first post.
A physical phenomena that I know for a long time is that when an atom (let's say hydrogen) has an electron that make a quantum jump from a higher energy state to a lower it emits a photon. Suppose the hydrogen atom is isolated from the external...
I am trying to create a MATLAB function (M-File) that will create & play a sinusoidal waveform with the given amplitude (A), frequency (f), sampling rate (Fs), and time span (tspan). the function must produce a .wav file with a specified filename.
the MATLAB Function Format must be...
I was routinely checking a question in an Engineering Maths book as listed below:
The instantaneous value of voltage in an a.c.
circuit at any time t seconds is given by
v = 100 sin(50\pit - 0.523) V. Find:
(a) the peak-to-peak voltage, the periodic
time, the frequency and the phase angle...
Hi everyone,
On this page, only questions 4 and 5 I need help for. For question 4, I really have no idea, and there's no real "working" that I can show to really say that I've given it a crack.
For question 5 on that page, I thought along these lines:
In series circuits, voltage...
Hello
I want to ask that in all customers or house electrical lines AC voltage are forming sinusoidal waveform.
http://img20.imageshack.us/img20/3859/voltagewavwform.jpg
This kind of waveform exists or not, if exists, so in were?
And can we check waveform of any voltages or...
I'm doing some past exam papers to revise for my test on thursday. And I can't work out the last question in this problem.
I worked out the time for one complete cylce is 50 microseconds, and the frequency is 20,000Hz, 1/Time period. I can't work out the last bit though.
Hi there,
I am trying to obtain the waveform due to random binary phase-shift keying. the graph is similar to a sinc/sampling function. Can someone help how to go about it?
regards
kautilya
I guess I am just bored, but I was wondering why we assume light travels in a straight line and not treat it like a waveform as I was taught in school. As far as I can remember light waves each have a frequency. Why do we not take into calculation that it actually travels over a longer path...
Homework Statement
v = 60sin(458t + 60º)
Find the voltage of the waveform when t = 5ms
It may be a silly question but I've just started studying ac, just wondering how that + 60º affects the equation?
any help would be appreciated as I've looked everywhere for the method...
Okay, I don't know if this is the proper place for this or not, so if it needs moved, move it. But here's my question. If the EM spectrum has no upper limit. Is it possible to have a waveform who's wavelength is twice the size of the known universe? This would put the observable universe within...
I'm having a problem with that integration part.
The average value of i^2 in one cycle = (sum of all i^2 in that period)/(that period).
To derive (sum of all i^2 in that period) we use integration, but that gives the area, how can the area be a substitution for this?...they are different...
A 20Hz TTL waveform is applied to the circuit...
The Attempt at a Solution
- I'm working an activity for my lab tomorrow (not actually due for any points, just to help us get an understanding of the lab), but I'm not really sure what it means when it says a "20 Hz TTL waveform"...
Hi,
This is my firs post to this forum.
This may be a trivial question but got a bit confused in reading few texts.
Usually periodic waveforms are denoted as
A exp (jwt)
However, as I understand the exponent consists of
cos (jwt) + i sin (jwt) which is a complex number.
So...
Homework Statement
A sinusoidal voltage waveform is rectified so that it becomes a half-wave waveform (i.e. the bottom half has been "chopped off"). Determine:
i) The average p.d.
ii) The RMS p.d.
iii) The heat dissipated in a 200ohm resistor in 100sHomework Equations
P_{avg} =...
I have a 1sec serial data stream and my cheap PC based oscilloscope cannot capture it with good enough resolution where I can read the data.
What can I do to capture this serial data stream with good resolution? My scope has only edge trigger function.
I'm thinking of building a circuit...
Hello PF. I'm building a circuit that uses triacs to switch power on and off for a series of devices. However my teacher warned me that Triacs basically skip the zero part of the waveform, and that can affect digital devices, such as my computer.
I'm looking for a more in-depth explaniation...
Homework Statement
I am given two waveforms (a square wave and DC) that define the maximum allowable operating parameters for an LED. I wish to derive the maximum allowable fully-rectified sine waveform (120hz).
Square wave: 442mW peak, 0.1ms pulse width, 10% duty cycle
DC: 87mW
See...
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...
Say we have an inductor connected to an AC voltage source. Current will then lag voltage by 90 degrees.
Does the current maintain it's previous value (as if the inductor was not there) but 90 degrees out of phase, or is it still dependent only on voltage?
Rephrasing (in case that was poorly...
Hello All,
Does anyone know of a simple circuit (with op-amps or something) that can generate a backwards sawtooth waveform? In otherwords, the waveform would have a sharp rise time and then slop off linearly. (see attachment).
Thanks,
Jason O
Firstly let me say that I am a telecommunications engineer so I am not an expert in physics and I hope this question doesn't bother you.
In radiofrequency or microwaves metallic antennas are used for receiving a signal or waveform. The field induces a current on the metal and the wave signal...
hi all. hope everything is well.
Just some advice please:
want to measure the displacement of a car's shock absorber's piston. Plan on doing this using a linear variable diferential trasformer (LVDT). Those of you that are familiar with such a device, know that its chief operation is based...
I have to propose a circuit that converts a triangular wave potential waveform to a square wave potential waveform, that has a T=10ms and Umax= +4V (the triangular curve has the same T and Umax)
We have a capacitor of 4micro Farad and 3 resistance (1kΩ ; 250Ω ; 500Ω) andyou should use only one...
http://www.rfcafe.com/references/electrical/images/period5.gif
For the last waveform in the picture above. How would i go about writing an equation for f(t)?
Thanks in advance
Sketch the output voltage as a function of time. The AC voltage source is V_{o}cos(\omega)t with V_{o} = 10V and \omega = 2000rad/sec.
I have posted a diode circuit question in the attachment
Ok, I think it should be a sine curve with a 10 V amplitude but am not too sure about the period...
Nature "loves" the waveform
Nature "loves" the waveform; from our psychological states to quantum mechanical states, from the motion of the pendulum to the alternating current we use everyday, from the motion of stars and the planets to the tides on earth, we are surrounded by the wave nature...