Resonant frequency Definition and 93 Threads

Does anyone know why the resonant frequency of a grounded human is smaller when ungrounded?

Hi , I've been wondering is there a metal or some kind of material that can hold a magnetic flux like a transformer core iron and alloys usually do, but at certain frequencies have a resonant effect, like putting a let's say 100hz frequency in the primary winding could make the electromagnetic...

Hello guys! Is it possible to convert a natural frequency to resonant frequency with maybe some kind of formula? I was given a transfer function and I was asked to draw a root locus plot and determine the resonant frequency. I know how to get the damping ratio and natural frequency and the value...

The question is as follows, How do you determine the frequency at which different types of molecules resonate to, such as water molecules to microwaves?

So I have this PEC cylinder that I am illuminating with a plane wave. As we know it should resonate when lambda is twice the length of the cylinder. My adviser suggested to examine the phase of surface current, but I do not understand how it is relevant. Maybe I didn't get it right...

A 25.0-kg child in Red Deer pumps herself on a swing when she kicks upward on the downswing, thus changing the distance from the pivot point to her centre of gravity from 2.40 m to 2.28 m. 1)The resonant frequency of her swing before the kick is: ___ Hz, and the resonant frequency after the...

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...

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...

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. 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...

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...

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...

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...

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

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...

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...

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...

Hi all, I have a problem at work, I have been asked to work out the resonant frequency of an assembly within our mechanical face seal. We have a mass (the face) attached to springs that are preloaded. The springs are fixed at the other end and the face is also pressed up against the seat...

I don't understand when you have an AC Circuit that has a coil, capacitor and resistance. What factor will the resonant frequency change when the frequency is tripled?

Hey guys, As a hobby I've decided to pick up EE and I've been reading quite a bit and I'm interested in building some basic circuits and determining the SRF in some coils that I've wound. I have found that you can calculate SRF using this formula: ......(1/5) ...29.85 x (H/D) F =...

[SOLVED] Parallel LCR resonant frequency derivation for larger resistances There have been similar questions here before which I have seen, but I couldn't find an answer with the detail I require. Homework Statement I would like to derive an expression for the resonant frequency of a...

Homework Statement Name the two lowest resonant frequencies of a tuning fork; each tine is 18 cm long. Speed of wave is 420m/s... ignoring metal thickness. Homework Equations F= Velocity/Wavelength; l= wavelength/2, l= wavelength, l= 3/2wavelength, l= 2wavelength, l= 5/2wavelength...

Hello, I have a question on how to do something. I'm not sure whether calculus or trigonometry is needed. this is not a homework question. an object will move left and right of a center point in a sinusoidal motion. the period is always the same; the amplitude should change. at any...

Hello, I have a question about resonance. Say I want to emulate something in software that has a resonant frequency. It will be receiving pushes and pulls at various intervals, and I want the emulation to reflect how intensely it would vibrate at its resonant frequency as the result of those...

Hi I'm currently setting up a simple cantilever beam experiment. The cantilever will be positioned vertical and a spray force will be exerted from the left hand side, causing the plate to deflect. This deflection will be measured and recorded. My question is how do I calculate the...

How does one begin to derive the resonant frequencies of a multiple mass mass-spring system? (3-mass system) OK, so deriving this isn't a homework problem. I'd just like to know how. It's been a couple of years since I've taken a physics course. I was asked what the resonant frequencies of each...

Does the electromagnetic or acoustic resonant frequency of a hallow spherical object ever equal the circumference of that object? If not what are the formulas to calculate this? Thanks in advance.

When calculating the resonant frequency of a circuit, does it matter whether or not the components in that circuit are in series or in parallel? Say...for a simple circuit with three components in series with a voltage source (a resistor, an inductor and a capacitor for example). The resonant...

Homework Statement In the circuit below, find the resonant frequency (\omega_0) and Z_{IN}\left(\omega_0\right). http://img143.imageshack.us/img143/9845/problem1444dx4.jpg Homework Equations \omega_0\,=\,\frac{1}{\sqrt{LC}} The Attempt at a Solution The resonant frequency is easy to find...

Hello everyone! First post here! I have quite a specific question. I am investigating resonant frequency of biological matter with dimensions of about 1mm cubed. What I would like to know is... 1) does anyone know of any good journals which look into resonant frequencies of small...

Homework Statement resonant freq. in air for arbitrary length steel pipe with radius in the 3-8 cm range and wall thickness in the o.5 to 1 cm range Homework Equations unable to find a relevant equation The Attempt at a Solution

Hello All, I'm wondering if there is some nifty formula out there that will tell me how much wire I will need to wind a loop antenna if I know what the diameter of the loop will be and the frequency that I want to tune into? Thanks, Jason O

Hi,:approve: I want to know why if XL = XC in circuit which has only capacitor and inductive. The current will be mixmum not infinity because we know the rule which I=V\Z which z is impedance. so the z will be zore so the current must be infinity.:confused:

What is the formula to calculate the oscillating (resonant?) frequency of a series RC circuit with a constant DC voltage? For example the RC circuit shown at this site: http://www.mikroelektronika.co.yu/english/product/books/PICbook/2_02chapter.htm" How does this circuit resonate...

Recently I was handed a flyer for a new gadget that is being sold. It consists of two modules that are attached with sticky tape to the underside of ones gas tank. 'There are no batteries and no wires' yet the gizmo 'changes the resonant frequency for the gasoline in your tank, improving...

Hello, I have a question on resonant frequencies. Everyone knows the example of breaking a wine glass by singing an extended note at the resonant frequency of that glass. My question is: Can other objects be "broken" by this same process? For example, is it possible to produce the...

i have a cylindrical pipe with a fixed internal diameter and a variable length. how would i calculate the resonant frequency of water within it, given that the speed of sound in water is approx. 1398 m/sec?

I have been trying to figure out the acoustical resonant frequency of objects. I think their are engineering formulas that could be used. For example if you have a 1x1x1inch block square of iron, at what acousticaly resonant frequency would it be tuned to? I imagine the shape would have...