Let’s say we have a boat whose longitudinal axis is the y-axis (which goes into the screen in the figure below) standing upright in a still water .
##S## is the Center of Mass of the boat and ##C## is the Center of Mass of the displaced water.On ##S## lies the force ##\mathbf W##...
This is my first thread here, so let me know if I didn't adhere to a format i was to follow. I'm in the middle of a project depicting the change that an oscillation of fluid inside a drinking straw faces depending on the viscosity of the liquid.
For reference, this is exactly the same example...
Consider the following setup:
In this, let us set the pendulum 1 into motion. The energy gets transferred through the connecting rod and the other pendulum starts oscillating due to the driving force provided by the oscillating pendulum 1. Isn't it?
So the neighbouring pendulum starts...
I am reading "Coulomb and the evolution of physics and engineering in eighteenth-century France". There it is said in page 152 para 1 that "Coulomb found that within a very wide range, the torsion device oscillated in SHM".
My questions are:
(1) By just looking at the time period of the...
Hi everyone!
Sorry if I'm not able to work through this problem very much myself... I'm a Food Science student, and I'm trying to read an article about ultrasonic cutting when applied to apple slicing. From the papers they reference, the rapid vibrations on the blade reduce the friction...
Hi PF!
Do you know what the natural oscillating frequencies are for a 2D circular drop of liquid in an ambient environment (negligible effects)?
Prosperetti 1979 predicts the frequencies for both a spherical drop and bubble here at equations 5b and 6b. There must be a simpler circular 2D...
From the first part of the question, I was able to get the value of ω which will be the same for the next SHM.
But, I am having difficulties solving for the amplitude as I can't find the boundary conditions required to get the amplitude.
I tried to calculate the time the charged particle will take to reach the plane using the a and using d=1/2at² and found the t to be equal to root(4εmd/σq).
I guess the time period of oscillation will be double of t (by symmetry), i.e. 2root(4εmd/σq). I don't know if this is correct.
Since the spherical wave equation is linear, the general solution is a summation of all normal modes.
To find the particular solution for a given value of i, we can try using the method of separation of variables.
$$ ψ(r,t)=R(r)T(t)ψ(r,t)=R(r)T(t) $$
Plug this separable solution into the...
Let's try inputting a solution of the following form into the two-dimensional wave equation: $$ \psi(x, y, t) = X(x)Y(y)T(t) $$
Solving using the method of separation of variables yields
$$ \frac {v^2} {X(x)} \frac {\partial^2 X(x)} {\partial x^2} + \frac {v^2} {Y(y)} \frac {\partial^2 Y(y)}...
I understand the derivation of T= 2π√m/k is a= -kx/m, in a mass spring system horizonatally on a smooth plane,
as this equated to the general equation of acceleration of simple harmonic motion , a= - 4π^2 (1/T^2) x
but surely when in a vertical system , taking downwards as -ve, ma = kx - mg...
I don't really know where to start as this is not exactly my homework and I finished school some 15 years ago. I looked into my old high school notes, the last time I ever had anything about mechanical waves and sound. Unfortunately, we never learned anything about sound waves causing...
Hi. I'm trying to determine the frequency of an block (roughly a rectangular prism) when the oscillation is due to a shear restoring force. Here is a diagram:
In the derivation, ##\rho## is the density of the block,##G## is the shear modulus of the block, ##y## is the elevation of the element...
My first impression was that since the external force was constant it wouldn't make any change on the period of oscillation of the system. But on further thinking I found that if I were to only consider the one dimensional oscillation of the particle then the component of force along the string...
I first found the equilibrium points taking the derivative of the potential. ##U'(x)=U_0 a\sin(ax)##, and the equilibrum is when the derivative is 0, so ##U_0 a\sin(ax)=0## so ##x=0## or ##x=\pi/a##. Taking the second derivative ##U''(x)=U_0a^2 \cos(ax)## I find that ##x=0## is a minimum point...
It is true that at resonance frequency the phase-shift between input and output is 90 degrees, so my mind would think that this is ok. But I am kind of unsure because of the whole dividing by zero part.
If this isn't allowed: is there any way to calculate/measure the damping coefficient with...
Hi,
for ease of reference this posting is segmented into :
1. Background
2. Focus
3. Question
1. Background:
Regarding (one, linear, second-order, homogeneous, ordinary, differential) equation describing the force in a non-driven, damped oscillation:
F = m.a = -k.x - b.v
F =...
First I worked out the dispersion relations, which is pretty easy:
##M \ddot x_j = K x_{j-1} + K x_{j+1} - 2K x_j -mg \frac {x_j} {l} ## (All t-derivatives)
We know ##x_j## will be in the form ##Ae^{ijka}e^{-i\omega t}##
so the above becomes:
## -\omega^2M = K (e^{-ika}+e^{ika}-2)-\frac {g}...
Hello,
Suppose we have a simple oscillating spring mass system. The natural frequency will excite the system to have infinite amplitude. Suppose then, that we have that system on a table so that amplitude is limited. I'm imagining the high school experiment with the spring mass system on the...
According to the wiki entry 'Kuramoto Model', if we consider the ##N=2## case then the governing equations are $$\frac{d \theta_1}{dt} = \omega_i + \frac{K}{2}\sin(\theta_2 - \theta_1)~~~\text{and}~~~\frac{d \theta_2}{dt} = \omega_i + \frac{K}{2}\sin(\theta_1 - \theta_2),$$
where ##\theta_i##...
We know that the charge on capacitors as a function of time takes the general form of:
##Q(x,t)=qe^{ijka}e^{-i\omega t}##
The voltage at each capacitor:
##V_j = \frac 1 C (Q_j-Q_{i+1})##
From KVL we have differential equation of t-derivatives:
##LQ'' + RQ' = V_{j-1} - V_{j}##
##LQ''+RQ'= \frac...
First of all, I found a function of the distance of the object form the equivalence point in both cases. I got something like d=2d' where d is the distance at the first case and d' at the second. I did that because I wanted to find the frequency, and so first I need to find the period of...
Again I am really confused, but I just put the traveling wave as:
##\psi(x,t) = Dcos(kx- \omega t)## for positive x
##\psi(x,t) = Dcos(kx+ \omega t)## for positive x
Then I simply differentiated and plugged in ##x=0##
##F(t) = - T D k sin(\omega t)##
and from this
## \langle P \rangle = T D^2 k...
Homework Statement
https://imgur.com/gallery/PQx8SmXHomework Equations
EPE (elastic potential energy) = 1/2kx^2
GPE (gravitational potential energy) = mgh
The Attempt at a Solution
my attempt, https://imgur.com/gallery/lJDhwqD
[/B]
I feel like I've made progress considering the quadratic...
Homework Statement
A 200 g ball attached to a spring with spring constant 2.40 N/m oscillates horizontally on a frictionless table. Its velocity is 20.0 cm/s when x=−5.00cm.
What is the amplitude of oscillation?
Homework Equations
f=√(k/m) /2π
x(t) = Acos(2πft)
v(t) = -2πfAsin(2πft)
The...
Homework Statement
Harmonically fluctuating object. It`s full energy (E) is 3*10-5 J. Maximum force (F) on object is 1.5 * 10-3N. Period is 2 seconds (T) and starting phase (ƒ) is 60°. Need to write equation for these fluctuations.
E = 3*10-5 J
F= 1.5 * 10-3N
T = 2 s
ƒ = 60°
Homework Equations...
Homework Statement
It's an oscillation problem. I have to find the FIRST time when the spring-mass system will have E (mechanical energy) = K (kinetic energy), if x(t)=12sin(5t+3,5). (t is time in seconds, x is lenghtof the system in cm).
Homework Equations
E=1/2kA^2
K= 1/2kx^2
The Attempt...
Homework Statement
Calculate the harmonic motion equation for the following case
A=0.1m, t=0s x=0.05m, v(t=0)>0 a(t=0)= -0.8m/s^2
Homework Equations
x(t)= +/-Acos/sin ( (2pi/T)/*t)
The Attempt at a Solution
[/B]
A is given to be 0.1 so I simply place it into the equation. Now I have to...
Homework Statement
Homework Equations
Kinetic Energy =1/2*m*v^2
Spring Potential Energy = 1/2*k*x^2
Gravitational Potential Energy = m*g*h
The Attempt at a Solution
I am thinking to solve this problem using energy conservation but I feel that it is not possible to apply energy conservation...
Homework Statement
Two balls of mass m are attached to ends of two, weigthless metal rods (lengths l1 and l2). They are connected by another metal bar.
Determine period of small oscillations of the system
Homework Equations
Ek=mv2/2
v=dx/dt
Conversation of energy
2πsqrt(M/k)
The Attempt at a...
Homework Statement
Consider a rod of length ##L## and mass ##M## attached on one end to the ceiling and on the other end to the edge of a disk of radius ##r## and mass ##m##. This system is slightly moved away from the vertical and let go. Let ##\theta## be the angle the pendulum makes with the...
Homework Statement
A light springboard deflects 15cm when a 65kg diver stands on its end. He jumps up and down, depressing it by 25 cm, then he moves up and down with the oscillations of the end of the board.
What is the amplitude of the oscillation when the diver just become airborne? What is...
Homework Statement
The period of oscillation of a nonlinear oscillator depends on the mass m, with dimensions M; a restoring force constant k with dimensions of ML-2T-2, and the Amplitude A, with dimensions L. Use dimensional analysis to show what the period of oscillation would be proportional...
Hello,
in every book and on every website (e.g. here http://farside.ph.utexas.edu/teaching/315/Waves/node13.html) i found for driven harmonic osciallation the same solution for phase angle:θ=atan(ωb/(k−mω^2)) where ω is driven freq., m is mass, k is spring constant. I agree with it =it follows...
when in LC oscillation current flow from inductance to capacitor and charge is opposite polarity. why don't current flow in reverse of it and charging the capacitor in same manner as it was earlier.
Homework Statement
Is the time average of the tension in the string of the pendulum larger or smaller than
mg? By how much?
Homework Equations
$$F = -mgsin\theta $$
$$T = mgcos\theta $$
The Attempt at a Solution
I'm mostly confused by what it means by time average. However from my...
Is there some common parameter for DC power supplies that provides the maximum oscillation amplitude allowable at the output?
For some context - I would like to generate an oscillating signal powered by a DC power supply, but to prevent most of the oscillations reaching the DC supply I am going...
<Moderator's note: Spin-off from another thread: https://www.physicsforums.com/threads/does-red-shift-approach-infinite-near-time-zero.948696/.>
We do, however, have a lower limit, because of the solar neutrino experiment: too light and the neutrinos wouldn't have enough proper time to...
The potential energy of a particle of mass $m$ is $U(r)= k/r + c/3r^3$ where $k<0$ and $c$ is very small. Find the angular velocity $\omega$ in a circular orbit about this orbit and the angular frequency $\omega'$ of small radial oscillation about this circular orbit. Hence show that a nearly...
Homework Statement
The problem is question 2(a) in the attached pdf. I seem to find myself at a dead end and am not sure where to go from here - I will attach my working in a separate file, but basically I need to show that the oscillator passes/crosses over the x = 0 boundary at a positive...
Why is there an assumption that if neutrinos didn't have mass they would move at the speed of light? and how does the fact they oscillate prove they have mass?
1. Homework Statement
The 4.00 kg cube in the figure has edge lengths d = 8.00 cm and is mounted on an axle through its center. A spring ( k = 1400 N/m ) connects the cube's upper corner to a rigid wall. Initially the spring is at its rest length. If the cube is rotated 4.00° and released, what...
A ball of 100g, suspended from a pulley of a dynamometer, oscillates freely. The length of the pendulum thus obtained is 1m. What are the indications of the dynamometer when the ball is at the point A of it's trajectory? The maximum offset angle is 15 degrees.
Homework Equations
α - alpha...
Homework Statement
Homework Equations
F=ma
τ = Iα = rF
v=rω, a=rα
L = Iω
Center of Mass/Moment of intertia equations
The Attempt at a Solution [/B]
So right now I've tried to model the force acting on the ring as it goes around the peg, but I think centripetal force is involved and I'm not...
If a suspended pendulum bob is accelerated (in a car, for example), if you're in the accelerating frame of reference, you will observe the fictitious force which appears to act on the bob (as you're in the accelerating frame, the bob is not 'moving' so to speak, so to establish equilibrium you...
Homework Statement
[/B]
For differential equation of the form
## y''- y = 0 ##
BC is
## y(1) = B ##
which usually have general solution
## y(x) = C1 e^x + C2 e^{-x} ##
But this manual I am reading always want to go with general solution
## y = C1 \cosh(x) + C2 \sinh( x) ##
I assume...
In school we have numerous exercises that ask you to find the time when a body passes a certain point for the nth time in simple harmonic oscillation. But it is a bit mentally taxing to solve with the actual formula of x=Asin(ωt + φ), just because you have to sort out all the infinite solutions...