Resonant Definition and 205 Threads

Homework Statement A musicians tuning fork rings at A above middle C, 440Hz. A sound meter level meter indicates the sound intensity decreases by a factor of 5 in 4 seconds. What is Q of the tuning fork? Homework Equations Q=\frac{\omega}{2\beta}...

hi there..in some places, i saw the usage "the Q factor of parallel LC tank ckt" while in some others, the Q factor of the inductor used in tank ckt is given..are they same?? As far as i know,Q=wL/R is the thing for inductor ,where R is inductor's series resistance..is the formula same for the...

Most people in electronics know that the resonant frequency for a parallel LC network is given by w=1/sqrt(LC). But, few realize that when there is a resistor in series with the inductor, the resonant frequency is shifted downward. When I solve the equation for the resulting impedance, I...

Hello, I have been trying to better understand the effects of dielectrics in resonant cavities. I read that the addition of a dielectric in a resonant cavity will reduce the resonant frequency of the cavity. My questions: Is there any relation to the reduction of the resonant...

My first post here. :D usually this situation does not arise, but I am working on thin piezoelectric films. When a apply a alternating voltage on the electrodes, the film vibrates. Now this constitutes a LCR circuit which has a resonant and anti-resonance frequency. Since it is vibrating, it...

Hello everyone, Recently I have been studying cavity resonators. I noticed that all cavity resonators have air in them, but I was wondering what the effects would be if something other than air was used? For the sake of simplicity let's say we put a dielectric material in it with a...

Is it true that by finding exact resonant frequency we could ionize matter or split molecules? What is frequency to split water molecules into H+ and HO- ions? What is resonant frequency to split up hydrogen atom into proton and electron? Would spliting water molecule require less energy...

HI all, A parallel tank circuit at resonance has a theoretical infinite impedance. However due to the resistance of L and C some power is dissipated so a small current will flow from the source. If a parallel tank circuit is oscillated at it's resonant frequency and a capacitor (C2) is...

Homework Statement Resonances occur in many physical systems, and are often observed by measuring the frequency response of the system to an applied driving force. use the example of a damped harmonic oscillator to show how the lorentzian function serves as a good description of resonant...

I recently simulated a parallel resonant tank circuit on multisim. I put an oscope across the tank circuit and I get an AC signal, but what interests me is that it is amplitude modulated. The oscillations slowly build up in amplitude, hit a peak and then die back down. I think that the...

Hello :) , Does anyone know some good paper or book from were it's possible to learn physics behind of work of resonant tunneling diode(RTD)? In last semester I had course in ˝microelectronics and nanoelectronics˝ and we studied basic principle on which RTD works, and it was very interesting...

Hi, I am a student who's learning about quantum mechanics. I was reading about the RTD (Resonant tunneling diode) and I got the general idea. However, I was looking at a I vs V graph and came up with a question. Since Resistance = V/I, the inverse slope of the I vs V graph has to be the...

I'm working on a RFSF for the University of KY. It's essentially a giant coil, where the coil is the inductor, inductance L, with resistance, R. It will be attached to a chosen capacitor, capacitance C, and attached to an AC power source. The RFSF will operate at resonant frequency. I'm...

Since the old topic is locked, I had to post a new one about this (old topic here: https://www.physicsforums.com/archive/index.php/t-231156.html" ) People were talking about resonant frequencies for body parts and/or the entire body and someone was looking for a chart, not sure if this is...

In a damped forced harmonic oscillator the amplitude is determined by a series of paramenters according to : A = (Fo/m)/ (sqrt( (wo^2-w^2)^2+(wy)^2) ). where Fo= driving force, m=mass of spring wo=natural frequency of system. w=driving frequency y=damping constant. Now my...

Homework Statement Given this circuit: [PLAIN]http://img546.imageshack.us/img546/2921/resonance.png Homework Equations How does one find the resonant frequency? (Since there are no values for the components, I assume this means find the formula). The Attempt at a Solution I...

Hi All, First post and very new to this. I'm a bit of a Tesla fan and have been experimenting with a few designs after viewing many theories on YouTube and various web sites regarding Tesla's radiant energy research. In a nutshell my theory is this:- What if we build the equivalent of an RF...

In an AC circuit, where there is only one ideal inductor and resistor, the resonance frequency occurs if the impedance of the inductor is equal to the resistance of the resistor. Why? I hope you understood the question and looking forward for explanation. thanks!

1. okay, so I'm still struggling on trying to plot a graph for the relationship between the resonant frequency and the tension in a length of rubber cord, using standing waves. I've got that as the tension increases so does the frequency, and as length increases the frequency decreases. and...

some lines are called "resonant" Hi, I would like some explanation on a topic for which I do not find detailed literature online or in books. In photon absorption/emission processes by atoms, some lines are called "resonant" (for example, the 2P1/2 (or 2P3/2) to 1S1/2 transition of...

1. I have to find out the relationship between tension and resonant frequency in a length of rubber, using stationary waves. 2. I know there is an equation for the resonant frequency in a length of string, given as f= 1/2L * sqrt T/μ . I am however imagining that as this is a rubber band...

Hi everyone, So, resonance, are resonant frequencies and natural frequencies the same thing with a different name? If not could someone please explain the difference. Been searching for the answer for over an hour. Thanks in advance Peter

i wonder if anyone can make me to understand the phenomena of resonant transfer of energy. advanced thanks.

I'm trying to understand why the voltage in a series LC resonant circuit exponentially rises? Can anyone explain exactly what happens that creates the effect? I've been wonding if it the distributed capacitance of L becomes a voltage multiplier, or if it is a voltage wave reflection...

Homework Statement A 138 cm length of string has a mass of 4.98 g. It is stretched with a tension of 6.35 N between fixed supports. What is the wave speed for this string? What is the lowest resonant frequency of that wave? (wavelength) = 138cm = 1.38m M = 4.98g = 0.00498kg Ft =...

Homework Statement [PLAIN]http://img705.imageshack.us/img705/4462/40230468.jpg Homework Equations Power Factor = True Power / Apparent Power f = 1 / (2*pi*root(LC)) Z = root(R^2 + (Xl - Xc)^2) = R The Attempt at a Solution a)i) 1? Because it's purely resistive, but this...

hi all i have a problem in finding the quality factor of cantilever beam (one end is fixed and other end is free ) vibrating in air /other medium? how the qualtiy factor expression for beam is calculated? whether all these expressions applicable to micro and nano cantilevers. please explain...

hi all i have a problem in finding the quality factor of cantilever beam (one end is fixed and other end is free ) vibrating in air /other medium? how the qualtiy factor expression for beam is calculated? whether all these expressions applicable to micro and nano cantilevers. please explain...

For a science investigation, I want to investigate how different factors affect the resonant frequency of wineglasses, however, I need some way to measure the frequency quantitatively. Is there some kind of computer program that can do so through the computer microphone? And if so, would the...

In anomalously dispersive media, the change in phase velocity with wavelength is negative; that is dv/dλ < 0. I wanted to ask: (a) whether you could fit a wide range of frequencies into a resonant cavity by taking advantage of anomalous dispersion (b) whether a material like this exists...

Homework Statement Hollow tube chimes are made of metal and are open at each end. One chime is 0.54 m long. A) if the speed of sound is 346 m/s, what is the frequency of sound produced by the third resonant length? B)What would happen to the frequency of sound produced by the third...

Is there a model for determining the self resonant frequency of a flat spiral inductor? I can determine the inductance but the capacitance is escaping me. Thanks for any help.

Homework Statement What kind of pipe can never have a resonant mode with a node in the exact center? (choices are closed on both ends, open/closed on one end only. open on both ends) why? Homework Equations none given The Attempt at a Solution I think its closed on both ends...

astrophyscs: question about nearly resonant orbits Homework Statement are any planets in low-integer resonant or nearly resonant (within two or three percent) orbits Homework Equations p2/p1 The Attempt at a Solution ok suppose to find for the planets of 55cancri so like 55cancri b...

Hi, I am trying to work out the resonant frequency of an annular ring, does anyone know a general equation for it? For example the ring has an outside diameter = OD and inside diameter = ID. The ring is gently clamped at the outside diameter and a force F applied evenly at the inside...

Hi I was wondering if someone would be kind enough to help me with a project I have at the moment. Here is the scenario; I am playing various tones through a speaker system at a fridge and I need to be able to detect which of the tones make the fridge resonate. I have been using a...

I did this in ANSYS, but I am wondering what is the analytical solution to this. Does anyone know?

In the case of a loop antenna with uncompensated inductance, the magnetic field generated by the current in the antenna is in antiphase to the incoming magnetic field of the EM wave. So it is believable that the current which causes cancellation of the flux through the antenna is the maximum...

(Is there one?) What is the Earth's natural resonant frequency?

Something is bothering me about passive systems in resonance. Consider the Bode plot of a second-order system, for example: http://en.wikipedia.org/wiki/File:Harmonic_oscillator_gain.svg Let's say we excite this system near its resonance, so the system has a gain > 1. I don't understand...

This question relates to the design of a Tesla coil, which is basically a loose-coupled, tuned transformer. The secondary is a series LCR circuit that develops a high voltage across a capacitor. The capacitor takes the form of a toroidal 'top-load' to ground. In the literature, much...

Homework Statement Consider pipe of length L. The pipe is closed at one end and open at the other allowing a standing wave where a node exists at the closed end and a max exists at the open end. a) what are the resonant wavelengths? b) If L=5, what is the lowest frequency? Homework...

I happened to sit in a presentation where the presenter displayed 2 separate values for resonant frequency and natural frequency. It was my understanding that the both are same and now I am in doubt. Please explain - if there is and you know - the difference between resonant frequency and...

Friends, I am trying to consider an impurity which can be viewed as a 1D resonant-tunnelling problem. I gather that the transmission coefficients TL and TR will decay exponentially from the impurity to the edges of the barrier. However, I am unsure how to predict how the peak & area of T(E)...

Homework Statement Hello, so I'm trying to solve the transfer function for a parallel RLC filter that goes like -------Resistor ------------------- |XXXXXXXXXXXXXXXXX|XXXX| |XXXXXXXXXXXXXXXXX|XXXX| VinXXXXXXXXXXXXXXXXCXXXXL |XXXXXXXXXXXXXXXXX|XXXX| |XXXXXXXXXXXXXXXXX|XXXX|...

Hi, here is the question: For part b) I have to find the amplitude of Vc at the resonant frequency with I=1A, I have found Zeq and well here are my equations: \frac{jwL+R}{\ jwRC-w^2LC+1} and I have the equation for w at the resonance:w= \sqrt[2]{\frac{L-R^2C}{\L^2C}} I know at the...

Homework Statement For a given rectangular waveguide the cut off frequency of the fundamental mode is 6.5GHz. What is the fundamental resonant frequency of a 30mm long cavity made from the same waveguide? Homework Equations Unsure The Attempt at a Solution I would have...

hello, im a quite stuck on how to answer this question on resonant circuits. any help would be most appreciated! Homework Statement a coil of inductance 220mH and resistance 6 ohms is connected in parrallel with a capacitor across a 230volt variable supply. if the circuit goes into...

Homework Statement Hi, I'm new to this forum. I'm a musician and recording studio owner. I'm not good at physics although I read "The Physics Of Music" and I am interested when in physics when it concerns musical instruments in particular. What I would like to know is a formula to...

Homework Statement An AC circuit consists of an alternative emf of 1 V connected to a resistor of 500 Ohms, an inductance of 0.4 mH, and two capacitors connected in parallel of 50 pF each, We want to find the resonance frequency of this circuit, the maximum power dissipated by the...