Harmonics Definition and 264 Threads

Homework Statement a 32 cm violin string with linear mass density is .36 gm/m is placed near a loudspeaker that is fed by an audio oscillator of variable frequency. It is found that hte string is set into oscillations at frequencies 1320 Hz and 1760 Hz as the frequency of the audio oscillator...

Hi, I have build an 12VDC- 12VAC inverter using a square wave gate signal for my power MOSFETs. My output is perfect square wave and now i want to clear the harmonics except the fundamental. I am not sure how can i design the analog filter that can filter the harmonics except the...

Could someone validate if this is correct? for waves with antinode/antinode or node/node ends if the fundamental frequency is f1 then f2 = 2f1, second harmonic and f3 = 3f1, third harmonic but for waves with antinode'/node or node/antinodes at the ends then if fundamental frequency is...

Homework Statement A system's wavefunction is proportional to sin^2p. What are the possible results of measurements of Lz and L^2? Give the probabilities of each possible outcome. I'm using p for theta and q for phi. Homework Equations The Attempt at a Solution So I believe that the value of...

This is something I wanted to do, but I don't know where to start. Given an alternating signal (not necessarily sinusoidal) if you wanted to double the frequency of the signal, where would you start?

Homework Statement The angular part of a system’s wavefunction is <\theta, \phi | \psi>\propto (\sqrt{2}\cos\theta + \sin{\theta}e^{−i\psi} - \sin{\theta}e^{i\psi} ). What are the possible results of measurement of (a) L^2 , and (b) L_z , and their probabilities? What is the...

Homework Statement Given the first harmonic, with length L, of a certain standing wave, what is the process for coming up with the next 3 harmonics for it?Homework Equations velocity = wavelength * frequencyThe Attempt at a Solution I don't understand how to draw the "next harmonic". I've come...

Am I correct in stating that the number of *anti nodes* in a STRING denotes the harmonic and the number of *nodes* in a OPEN TUBE denotes the harmonic? -Thanks

Homework Statement Hi! I need help with this. I have to calculate the expression of a function using spherical harmonics. The relevant equations are given below. An example of a function can be f(theta,phi) = sin(theta)... Can you help me to calculate de coeficients and to express the...

Homework Statement A flute is essentially a pipe open at both ends. The length of a flute is approximately 66.3 cm. The speed of sound in the flute is 342 m/s. What is the first harmonic of a flute when all keys are closed, making the vibrating air column approximately equal to the...

Dear people. I am working on music theory and I am making a program to derive musical scales, but I need a name for the interval of combining to harmonic intervals. Etc. if I multiply 4/3 with 5/4 I get 5/3. But what is the correct words for such intervals (except that a few of them actually...

Whats a good book to learn about these topics?

I would appreciate some input about how to program spherical harmonics in Matlab. http://mathworld.wolfram.com/SphericalHarmonic.html I want to program a double summation that looks like this. G(\Omega_{1},t_{1}|\Omega_{0}) = \sum_{l=0}^\infty \sum_{m=-l}^l...

Homework Statement A problem with odd harmonics only. Show that the solution of the heat equation du/dt=c2*(d2u)/(dx2), subject to boundary conditions u(0,t)=0 and ux(L,t)=0, and the initial condition u(x,0)=f(x) , is u(x,t)= \sum Bnsin[(\pi/2L)(2n+1)x]e-((c*\pi/2L)*(2n+1))^2 where n...

expansion of polarized plane waves into spherical harmonics, please help! Hi all, I would like to get some guidance in how to expand a polarized (i.e. linear polarization) plane wave into a series of spherical harmonics. I am aware of the formula applying to scalar plane waves (please see...

I wonder if you can recommend a good book treating "Spherical Harmonics" in some details. Thanks for help

Would a harmonic of the Larmor frequency have any effect on proton precession?

Hello, I am confused in some areas of this topic at school and i was wondering if you guys knew any good tutorials online that i could learn from. Tried a few sites but they are "wayyy" above my head. The things i need to know is like, the angles in radians, diplacenment, acceleration, speed...

Homework Statement The frequency of a tuning fork can be found by the method shown in Figure 13-24. A long tube open at both ends is submerged in a beaker of water, and the vibrating tuning fork is placed near the top of the tube. The length of the air column, L, is adjusted by moving the...

A high voltage capacitor is charged and then the two leads are shorted together generating a spark, simultaneously a nearby radio crackles. This shows us that when the spark was generated radio waves was also generated. These primitive radio waves are sometimes called hertzian waves. A bolt of...

[SOLVED] Open ended pipe Harmonics Mastering Physics Question Homework Statement Consider a pipe 45.0cm long if the pipe is open at both ends. Use v = 344m/s. Now pipe is closed at one end. What is the number of the highest harmonic that may be heard by a person who can hear frequencies...

The question is exactly this: Prove that the maximum speed (Vmax) of a mass on a a spring is given by 2(pi)fA. where f = frequency and A =Amplitude We are given such formulas as: f=[1 / 2(pi)]square_root (k /m) or f=[1 / 2(pi)]square_root (a /-x) the formula for total energy in a...

If you vibrate a tuning fork over a closed pipe (a pipe with one end closed and the other open) is it possible to get overtones in the pipe even thought the tuning fork only vibrates at one frequency For example if you have a tuning fork of freq 300HZ and you allow it too vibrate above a closed...

I have been torturing myself with this problem for a couple weeks now and I am stumped. The unit I am working on is called simple harmonics. The question is: Prove that the maximum speed (Vmax) of a mass on a spring is given by 2(pi)fA I am guessing that the question wants me to re-arrange one...

Right, I'm new to this forum but not new to asking daft questions. So here we go. Just Imagine I'm sat in my shed and I've got a battery hooked up to a purely resistive load with a switch between the two. In adition I've set up a tuneable antenna in close proximity. If I turn the switch...

[SOLVED] Plz help w/ Simple harmonics question I am doing simple harmonics and running into problems. The formulas given for simple harmonis in my book are f=[1 / 2(pi)]square_root (k /m) or f=[1 / 2(pi)]square_root (a /-x). The question reads: Car 1 has a...

Homework Statement A tuning fork is set into vibration above a vertical open tube filled with water, as seen in the figure below. http://capaserv.physics.mun.ca/giancoli-calc/Graphics/Graph16/dgian1686.gif The water level is allowed to drop slowly. As it does so, the air in the tube above...

That is all that is needed, three would be too complex, one can get the harmonics from two, it hard to imagine there being three, but may be the third is an echo ?

Homework Statement Why is is the for physical applications of the spherical harmonics |m| must be less than or equal to l, with both being integers? Homework Equations Y(m,l)=exp(im phi)P{m,l}(cos theta) Hopefully my notation is clear, if not please say. The Attempt at a Solution Well...

Homework Statement At t=0, a given wavefunction is: \left\langle\theta,\phi|\psi(0)\right\rangle = \frac{\imath}{\sqrt{2}}(Y_{1,1}+Y_{1,-1}) Find \left\langle\theta,\phi|\psi(t)\right\rangle. Homework Equations \hat{U}(t)\left|\psi(0)\right\rangle =...

[SOLVED] Simple Harmonics Homework Statement A 10.0 kg mass is traveling to the right with a speed of 2.40 m/s on a smooth horizontal surface when it collides with and sticks to a second 10.0 kg mass that is initially at rest but is attached to a light spring with force constant 75.0 N/m...

Homework Statement I want to expand sin(theta) in spherical harmonics. Well, actually I want (3cos^2(theta+45°)-1)*exp(i*(psi+45°)) but I think I could find my mistake by the above simple example. Homework Equations http://en.wikipedia.org/wiki/Spherical_harmonics The Attempt at...

[SOLVED] Simple Harmonics - Kind of wierd Homework Statement Question: A 1.30 kg mass on a spring has displacement as a function of time given by the equation: x\left( t \right) = \left( {7.40\;{\rm{ cm}}} \right)\,\cos\:\left[ {\left( {4.16\;{\rm{ s}}^{ - 1} } \right)t - 2.42}...

[SOLVED] Simple Harmonics Question Homework Statement A 1.40 kg ball and a 2.20 kg ball are glued together with the lighter one below the heavier one. The upper ball is attached to a vertical ideal spring of force constant 170 N/m, and the system is vibrating vertically with amplitude 19.0...

Homework Statement What fraction of the energy of a square wave is in its fundamental? In its first five harmonics? First seven? Nine? Homework Equations the Fourier series of a square wave... v(t) = ( 4V / pi ) ( sinw0t + 1/3sin3w0t + 1/5sin5w0t + ... ) also given a graph showing...

Homework Statement A. A string with a mass density μ = 4.10×10-3 kg/m is under a tension of F = 327 N and is fixed at both ends. One of its resonance frequencies is 742.0 Hz. The next higher resonance frequency is 1113.0 Hz. What is the fundamental frequency of this string? B. Which harmonic...

Homework Statement An organ pipe is 1.70 m long and it is open at one end and closed at the other end. What are the frequencies of the lowest three harmonics produced by this pipe? The speed of sound is 340 m/s. Only one answer is correct. 200 Hz, 400 Hz, 600 Hz 200 Hz, 300 Hz, 400 Hz 200...

This isn't exactly a part of any problem, but a part of a generic principle. I don't understand the use of raising and lowering operators. L_{^+_-}=\hbar e^{^+_- i l \phi}({^+_-}\frac{\partial}{\partial \theta}+ i cot \theta \frac{\partial}{\partial \phi}) So how does one use L_{^+_-}Y_l^m...

Homework Statement I want to expand 1+sin(phi)sin(theta) in the spherical harmonics. I am not sure if this will be an infinite series or not? If it were infinite that would seem rather difficult because the spherical harmonics get really complicated when l > 3. Also, all of the sine terms in...

I'm having a bit of a difficulty trying to determine the fundamental frequency in a given function and the harmonics. In the equation below,would the fundamental frequention be 1 (corresponding to the value cos(1x-pi)) and the harmonics amplitude 3 and -4?Also,the values of the frequency of the...

Homework Statement The spherical harmonics Y^m_l with l=1 are given by Y^{-1}_1 = \sqrt{\frac{3}{8\pi}}\frac{x-iy}{r}, Y^0_1 = \sqrt{\frac{3}{4\pi}}\frac{z}{r}, Y^1_1 = -\sqrt{\frac{3}{8\pi}}\frac{x+iy}{r} and they are functions of L^2 and L_z where L is the angular momentum. i) From...

Harmonics of a Square Wave... Homework Statement A 200kHz square wave with a fundamental frequency amplitude of 15V. Find amplitude of the third harmonic. Homework Equations This is what I do not know. I know this is a Fourier transform problem but just don't know what to do with...

Homework Statement A 8.3 kg mass slides on a frictionless surface and is attached to two springs with spring constants 28 N/m and 62 N/m that are on either side of the mass. Find the frequency of oscillation. Answer in units of Hz. Homework Equations (2pi sqrt(m/k))^-1 The...

String A is stretched between two clamps separated by distance L. String B, with the same linear density and under the same tension (i.e., having the same wave velocity) as String A, is stretched between two other clamps separated by distance 4L. Consider the first 8 harmonics of string B. For...

i'm a flautist. sometimes i have to play notes called harmonics, where the finger position is the same (i.e. same holes closed off) but you have to vary the air speed so that you can hear the original note and also another note above it in pitch. can anyone explain to me why it is that i can...

Hi, I'm trying to get the Y_l^l spherical harmonic and I'm running into problems evaluating the following expression: \frac{d^{2l}(\cos^2(\theta) - 1)^l}{d\cos(\theta)^{2l}} The 2lth derivative with respect to cos theta of cos squared theta - 1 to the lth power it just seems like I'm going...

Hi, I am a bit puzzled by a physics problem. I had to calculate the force on a wire and its second harmonic. Given data were, the diameter of of the string 1,2 mm , length of 1,25m. Density of steel 7,8 kg/dm^3, its fundamental frequency is 300 Hz, and also one end is fixed the other is...

Happy New Year all! i have a question regarding the addition theorem for spherical harmonics. In JD Jackson book pg 110 for e.g. the addition theorem is given as: P_{L}(cos(\gamma))=\frac{4\pi}{2L+1}\sum_{m=-L}^{L}Y^{*}_{Lm}(\theta',\phi')Y_{Lm}(\theta,\phi) where...

In finding harmonics do you just multiply the harmonic number times the frequency? Find the first four harmonics when f=343Hz would be f1=343Hz, f2=686Hz, f3=1029Hz, and f4=1372Hz. This just seems too easy.

I'm calculating the zz Component for the quadruple tensor. Q_{zz} = 3cos^2\theta-1 (r=1 in this case), and the Y_{lm}(\theta,\phi) would be l=2, m=0. I would like to calculate the result in either maple or mathematica - I have not used either very much - I want to check the result using...