Vibrating Definition and 148 Threads

Homework Statement A particularly beautiful note reaching your ear from a rare Stradivarius violin has a wavelength of 39.1 cm. The room is slightly warm, so the speed of sound is 344 m/s. If the string's linear density is 0.560g/m and the tension is 160N , how long is the vibrating section...

Hi I am very confused at determining the type of elastic wave in a vibrating body. For example, an elastic solid is flexuraly vibrating in one of its resonant mode. There should be elastic wave excited from this vibration. But, my question is which wave will be excited through it...

We have a region Ω in ℝ^2 with a smooth boundary. There is a plate of shape Ω and clamped edges which is approximated by the following equation: $$\frac{∂^2u}{∂t^2}=-Δ^2u$$ $$u(x,t)=0\hspace{4ex} x\in ∂Ω$$ $$Du(x,t)\cdot\hat{n}=0\hspace{4ex} x\in ∂Ω$$ \hat{n} is the outward pointing unit vector...

from this equation i get the amplitude is 8 cm, it's a sine function so i guess it has to be a harmonic oscillation i haven't had physics in a while so not really getting anywhere -i need to know T (time for one oscillation) -the frequency f which is 1/T -Vt and At equations, i know i...

I am trying to get a better understanding of what it means for an atom to vibrate. Let's say there is a chunk of iron in deep space that starts out with a temperature of 50 degrees celsius and is rapidly losing thermal energy. I will make the following assumptions: 1. The iron has thermal...

Homework Statement Homework Equations The Attempt at a Solution

The online edition of an italian newspaper, reported the curious event of a street pole which seems to vibrate for prolonged times, hours, even an entire day and without any clear reason. Someone talks about a building site in the nearby area, other talks about a wind turbulence called "vortex...

Homework Statement I keep getting the wrong answer for this question: A taut spring for which μ = 0.05 kg/m is under tension of 80.0N. How much power must be supplied to the string to generate sinusoidal waves at a frequency of 60Hz and an amplitude of 6cm? Homework Equations ω = 2∏f...

Hi all, According to quantum theory, for an electron vibrating in one dimension, only probability of position is meaningful. My question is will there be a e&m radiation by such a motion, if yes, how to appreciate it from the possibility argument, say, if only the probability at each position...

Homework Statement For a zero initial deflection and for a finite initial velocity, the time dependence of the vibration response of an overdamped system to an impulse is given by: (1) θ(t)=[I/(mω)√(ζ^2-1)][e^-(ζωt)][cosh(ω√(ζ^2-1))t] which for large values of time becomes: (2)...

Here is a tricky one (for me) that uses linear mass density and two masses. I don't really know which to do so I did both! Homework Statement An object can be hung from a string (with linear mass density μ=0.00200kg/m) that passes over a light pulley. The string is connected to a...

If we had a beam fixed at $x = 0$ and on pin rollers at $x = L$, why would $u_{xx}(L,t) = 0$ and $u_x(0,t) = 0$. $u(0,t) =0$ since the at $x = 0$ the beam is fixed and $u(L,t) = 0$ since the beam is on roller and wouldn't have any displacement, correct?

Suppose a cantilever beam stands uprigt, such as a tube attached to the floor in one end and free at the other end. Suppose then that a force is applied normal to the beam at some point along the beam causing a deflection. Then suppose that at t=0 the force disappears, and the intertia of the...

Homework Statement "Vibrato" in a violin is produced by sliding the finger back and forth along the vibrating string. The G-string on a particular violin measures 30cm between the bridge and its far end and is clamped rigidly at both points. its fundamental frequency is 197Hz (a) how far...

Homework Statement Sound Wavelength From String During a concert a pianist hits a key that sets up a standing wave in a piano string that is vibrating in its fundamental mode. The string is 0.5 m long, has a mass density of 0.002 kg/m and is held under a tension of 120 N. What is the wavelength...

Dear all, We are in need of a vibrating sample magnetometer for our lab. but don´t have the money to buy a new one. We are considering - buy a secondhand one (still expensive) - buy the VSM head and adapt to a existing magnet. If you now where to find one, I would be happy to hear from...

Homework Statement (∂^2 u)/(∂t^2 )=a^2 (∂^2 u)/(∂x^2 ) x∈(0,l) t>0 u(0,t)=0 ; ∂u/∂x(L,t)=0 u(x,o)=u1; ∂u/∂t(x,o)=x I can not figure out physical interpretation of boundary condition ∂u/∂x(L,t)=0, what does it mean. Can someone can help me with this ? Homework Equations The...

So as the title says, what is a vibrating system? Does it only apply to sound waves? Please give five examples of everyday vibrating systems just to contextualise the concept for me. Many thanks

Homework Statement Consider an object consisting of two balls connected by a spring, whose stiffness is 400N/m. The object has been thrown through the air and is rotating and vibrating as it moves. At a particular instant the spring is stretched 0.3m, and the two balls at the ends of the...

Homework Statement A vibration platform oscillates up and down with an amplitude of 10.4 cm at a controlled variable frequency. Suppose a small rock of unknown mass is placed on the platform. At what frequency will the rock just begin to leave the surface so that it starts to clatter? Homework...

Homework Statement A tiny vibrating source sends waves uniformly in all directions. An area of 3.25 cm2 on a sphere of radius 2.50 m centered on the source receives energy at a rate of 4.20 J/s. (a) What is the intensity of the waves at 2.50 m from the source? (b) What is the intensity of...

Hello all, Homework Statement A vibrating string 50.0 cm long is under a tension of 1.00 N. The results from five successive stroboscopic pictures are shown. The strobe rate is set at 5000 flashes per minute, and observations reveal that the maximum displacement occurred at flashes 1...

Homework Statement Consider a string of infinite extent made up of two homogeneous strings of different densities joined at x=0 In each region utt-c2juxx=0 j=1,2 c1≠c2 we require continuity of u and ux at x=0 suppose at t<0 a wave approaches x=0 from the left. IE: as t approaches...

Homework Statement The equilibrium separation of the atoms in H35CI equals 1.27 x 10-10m. Calculate the energy separation between adjacent lines in the rotational-vibrational spectrum Homework Equations E = (n + 1/2)h\omega + h2/ 2I * l(l+1) I = \mur02 \mu = m1m2/ m1 + m2 The...

When you listen to music, you hear the beat, the melody, and the vocals all at once... and they all emanate from the same disk. How does all the noise sound so separate and distinct from one another regardless of whether its a rumbly bass or a piercing pitch? This confusion comes from my...

How do we describe vibrating strinGs and branes? Is this connected with vibration of circular or quadratic membrane and PDE Helmholtz equation and how? How to test string theory in experiments?

I'm looking for an equation and I am not quite sure where to start, and am hoping someone could direct me to a good reference to some similar type equations, or at least kick me over to the proper forum. I am looking for an equation that describes the energy distribution within the space...

Homework Statement Determine fundamental frequency of a vibrating string if two successive harmonics of the string are 180hz and 270hz Homework Equations f=1/t t=1/f The Attempt at a Solution I want to say its just f=1/t for both of them but it seems to easy?no?

I read that the middle point of a string fixed between two rigid supports set in its fundamental mode of vibration has no potential energy. I would like to know the reason behind it. At the max displacement from the mean position, it must have max. potential energy.

I'm doing a project on a vibrating guitar string and I have completed all the simulation and experimental work, but I do not fully understand the theory behind it. I need to derive the 1 dimensional case of the wave equation, as the 1 dimensional case is considered to be the most convenient...

I set up a simulation of a vibrating guitar string after it has been impulsed (plucked). It is in tension, and all of the parameters are set up so that it vibrates at a fundamental frequency of 196Hz, and the software has confirmed that this is indeed the fundamental frequency of the string at...

Homework Statement In the midst of Forced Vibrating Membranes and Resonance Utt = c^2*delsquared(U) + Q(heat source) Arrive at eigenfunction series solution where the coefficients are given by d^2/dt^2 (A_n) + c^2*lambda_n*A_n = q_n Homework Equations according to the book, I am supposed to...

I'm running a finite element simulation of a vibrating guitar string, but I do not know how to calculate the correct damping factor for the string as it oscillates in air. I don't have information regarding how many times it will oscillate before the oscillation damps out, but I do have all the...

Homework Statement A tuning fork, frequency 388Hz, is mounted vertically on a ring stand. A string of length 2m is attached to the tuning fork, and a mass m is hung at the end of the string. The tuning fork is activated, and a wave passes through the string (wavespeed 600m/s.) Assume the...

Homework Statement The fundamental frequency of a vibrating stretched string of length 1.0m is 256Hz.When the string is shortened to 0.4m with the same tension,the fundamental frequency now become how many Hz? Homework Equations The Attempt at a Solution

Homework Statement How to calculate the radiation from i) vibrating ii) rotating ellipsoid? Homework Equations The Attempt at a Solution Rotating ellipsoid has a time dependant dipole moment so the radiation pattern will be of electric dipole type (The magnetic dipole and...

Homework Statement A narrow plastic pipe is almost completely submerged in a graduated cylinder fulll of water, and a tuning fork is held over its open end. The pipe is slowly raised from the water. An increase in loudness of teh sound is heard when the pipe has been raised 17 cm and again...

Homework Statement (a) An aluminium wire of length L1, cross-sectional area A and density ρ1 is connected to a steel wire with the same cross-sectional area and density ρ2. This compound wire, loaded with a block of mass m, is arranged as shown below so that the distance between the joint and...

Homework Statement The problem is as follows: there is a beam of length L pinned at both ends. A force F is acting in the middle. I must plot the velocity of this system at a point L/3 from the right. This is a continuous system so I am to use the pde approach. Homework Equations I'm...

Homework Statement An aluminium block of m is hung from a steel wire of length L. The fundamental frequency for transverse standing waves on the wire is 300 Hz. The block is then immersed in water so that half of its volume is submerged. What is the new fundamental frequency? (You may assume...

Homework Statement Find mass of vibrating steel cantilever. It is fixed at one end and got a mass on the other (free) end. Find the mass required when it is vibrating at w(natural) = 1800 rev/min. Lenght: 50mm width: 7mm Thickness: 1mm Homework Equations w = sqrt(k/m) The...

Homework Statement Two ukulele strings, of equal length and mass are tuned so that the first string, when it vibrates at twice its fundamental frequency, has the same frequency as the second string when it vibrates at three times its fundamental frequency. The tension of the first string is...

I was wondering the critical load vary as a result of forced vibration? Intuitionally, I thought the critical load reduced. But how to show it analytically, Any idea?

We recently had a thread on https://www.physicsforums.com/showthread.php?t=440768". What about a string? After it is randomly plucked, what model explains why the many very high order modes decay so much quicker than the fundamental resonance mode does? A similar example (if this might be any...

Homework Statement In textbooks, I often see the sum of the first two normal modes given in the equation attached (on the right). I'm wondering how they arrive at that equation based on the general formula (on the left). I tried subbing in n= 1 and 2 in the general formula, but I'm not sure...

Prove that there are n-1 nodes on a string fixed at both ends for the nth harmonic. It is simple to show this using a diagram. [PLAIN]http://www.space-matters.info/img/nodesandmodes.jpg However, is there a way to show this mathematically?

Differential Equation Help -- Vibrating String Homework Statement Suppose a tightly stretched vibrating string has a variable density \rho(x). Assume that the vibration is small and is only in the vertical direction (transverse-vibration). Derive teh PDE taking into consideration the gravity...

Calculate a VIBRATING FEEDER ? Hi everyone! how i calculate the flow in a vibrating feeder? What data should i use to solve a problem like this? i think that i would need the center of mass of the feeder the power of the magnetic or the unbalanced vibrating feeders? can someone explain...

Hello. Let's assume I have a thin metal stick (or other material) anchored to a wall at one extremity (A), and free to move on the other extremity (B). If I push down the extremity B and then release it, the stick starts to vibrate for some time (especially in the points closer to B). If I...

Hello, I am a biology student working on my masters and i have to control a small vibrating motor (like http://www.alibaba.com/product-gs/51129609/dc_micro_motor_vibration_motor_small.html) and have no experience with electronics and such. i would like the motor to vibrate for a couple of...