Problem:
Attempt at solution:
So "energy passing through per unit area per unit time" is equal to $$I = \frac{E_i}{A t}$$
So for a the graph will be in the form of ##y=1/x##?
For b) do we have to solve the differential equation $$dI = \frac{E_i}{A dt}$$?
This exercise comes from Kleppner and Kolenkow, 2nd ed., problem 6-3. I'm using a solution key as a study reference, but the solution key is coming to a pretty different conclusion. Mostly the issue is in the equations of motion for this system. I'm not sure if there's something I'm...
Hello! I have a plot of a function, obtained numerically, that looks like the red curve in the attached figure. It is hard to tell, but if you zoom in enough, inside the red shaded area you actually have oscillations at a very high frequency, ##\omega_0##. On top of that you have some sort of...
Consider the FLRW metric.
We pick a specific definition for the scale factor as suggested bellow.
Suppose we have a hypothetical metric having the scale factor defined by
## a(t)=\sin(t) (1+ \text {sgn}(\sin(t)) +\epsilon ##
Does this make sense, mathematically (and physically)?
Like having...
Hi;
This is in fact not a homework question, but it rather comes out of personal curiosity.
If you look at the graph of the two functions in the image attached, what is the simplest functional representation for such a symmetrical pattern?
yooo.
Some help on the following problem would be much appreciated.
I don't get how to solve the two equations I obtained for the COIs A and phi.
calculated: ##\omega == 7rad/s## and ##\gamma = 0.396s^-1##
for part C
we have two initial conditions:
at t = 0 > ##0 = Acos(\phi)##
at t = 1s >...
At first I tried plugging everything in with 60Hz in the numerator but that did not work. I was told to think about sinusoidal waves and derivates but I'm not sure how that works. Any ideas? Thanks a lot
In a problem of an oscillating electric dipole, under appropriate conditions, one can find, for the potential vector calculated at the point ##\vec{r}##, the expression ##\vec{A}=\hat{k}\frac{\mu_0I_0d}{4\pi}\frac{cos(\omega(t-r/c))}{r}## where: ##\hat{k}## is the direction of the ##z-axis##...
I am trying to numerically solve (with Mathematica) a relativistic version of infinite square well with an oscillating wall using Klein-Gordon equation. Firstly, I transform my spatial coordinate ## x \to y = \frac{x}{L[t]} ## to make the wall look static (this transformation is used a lot in...
Hi all!
I was wondering,
Is it possible, given a specific dipolar molecule, to create the perfect oscillating electric field so as to heat it and not, i.e. the water around it?
What I'm basically asking is could there exist a specific microwave just for X and not all dipolar molecules without...
Since it passes through the origin every ##3.6s## the period is ##T=3.6s## hence ##\omega=\frac{2\pi}{\omega}=\frac{2\pi}{3.6}\frac{rad}{s}## thus ##A=\frac{v_{max}}{\omega}=\frac{1.2}{\frac{2\pi}{3.6}}m\simeq 0.69m## and ##a_{max}=\omega^2 A=(\frac{2\pi}{T})^2 A=(\frac{2\pi}{3.6})^2 \cdot...
The oscillator's initial energy can be found by considering when all of its energy is potential energy.
Eo = (1/2)kA2 = (1/2)mω2A2 = (1/2)me(2πν)2A2 = 2meπ2ν2A2
where me is the mass of an electron. With this in mind, the energy dissipated after one cycle is given by
ΔE = E(0) - E(1/ν) = Eo -...
Hello everyone.
I am having some trouble with an RC phase shift oscillator that I built as a hobby project. I am completely stuck on this and I just cannot figure it out. My oscillator is not oscillating.
Here is the circuit that I am trying to get to work. Taken from...
The last couple of days I’ve been troubled with a specific part of electromagnetism. How will electric field lines be affected by an oscillating charge? More specific, what will happen with the “amplitude” of a wave in an electrical field line as the wave propagate away from the charge?
1. Will...
When an oscillator produces waves - let's say they are highly focused - that are damped by a second negative phase oscillator, where is the wave energy? The energy in each set of waves must still exist. Has it become hidden?
The "egg" initially spun around axis 1 with at ##\omega_s##. After being disturbed, it has started to possesses angular velocities along 2 and 3. The question is to find the rotational speed of ##\vec \omega=\vec\omega_1+\vec\omega_2+\vec\omega_3## to a fixed observer.
It is calculated that...
This problem honestly got me in big confusion.
I managed to find the angle ##\theta## at which the rod rests by equalling the components of weight and Lorentz's force... but from this point on I really don't know how to manage the harmonic oscillation part.
I know it is a quite simple task.
p = mv and F=ma.
All i need to do is find the normal and double derivatives of s(t). But here's the problem , i have the answers and they state that first derivative is v =
-Awcoswt and second is -Aw^2sinwt. Everything is quite clear to me, but I am wondering...
I thought we could do the part a by two steps:
(Studying the motion along x {there is no})
and along y
(Here should be T + dT)******
But apparently the answer is: ""
So i think if the answer is wrong or, if not, where i made a mistake?
The problem is easy to solve, the question i have is another about static.
Why when we get:
F = (-A*p*γ/l)y
Can't we just substitute p*a = m*g? If this is a oscillation, it will be about some equilibrium position, where the net force is zero and which was the initial position of the body, in...
I have general equation for undamped forced oscillations (no friction) which is:
I just wonder about,what type of motion should occur when initial conditions are both 0 (i.e v0=0 and x0=0). My intuitive expectation is that as there is no 'natural' oscillations at beginning,vibration has to be...
A mass (M) is attached to a spring (K). Mass moves in a one dimensional plane (horizontally)
1) If mass M is initially at x=0, what is the minimum Work required to bring it to x=x0 ? PE ?
2) M is released from x=x0, PE when x=xo/2 ? KE ?
3) PE when x=0 ? KE ?
4) PE when x=-x0/2 ? KE ?
5) What is...
First some background, then the actual question...
Background:
(a) Very simple example: if we take ##Asin(x+ϕ)+0.1##, the average is obviously 0.1, which we can express as the integral over one period of the sine function. (assume that we know the period, but don't know the phase or other...
Homework Statement: The amplitude of the oscillating electric field at your cell phone is 4.0 μV/m when you are 10 km east of the broadcast antenna. What is the electric field amplitude when you are 20 km east of the antenna
Homework Equations: electric field
i've done
E=##\frac A...
Hi PF!
I'm simulating two fluids, air (blue) and water (red), in a 2D rectangular channel. See picture below:
I've turned gravity and viscosity off, and have ##\rho_w=1000## kg/m^3 and ##\rho_a = 0.01## since it cannot be zero. I've also enforced a static contact angle of ##\theta = 71^\circ##...
Hello,
I have an equation relating the angular acceleration (d2Θ/dt2) of an undamped system to a forcing function and the an angular term (Θ). The system in question is an inverted pendulum. I know that such an oscillating system can be represented by the following function:
The problem is...
Tried to find the resultant force, but I can't see how the magnetic field affects. I used Faraday's law to find the the diferece of potentials in the plate Wich should be B.d.v, where v is the vertical velocity of plate, but there were not given the resistance or resistivity to relate with the...
Hello,
I've been studying electromagnetics, electromagnetic radiation, and bit of quantum electrodynamics for about 12 months, but I'm stumped on an issue..
This is what I understand so far:
Charge consists of countless "vacuum fluctuations" (i.e., virtual particles).
Accelerated charges...
Problem Statement: The amplitude of the undamped oscillation of the point of the string is 1 mm, and the frequency is 1 kHz. What path will pass a point of 0.2 minutes?
Relevant Equations: V=f x lamda
I don't understand the question. Please help
How can I get the Input Torque required to pump the double-acting cylinders with the following specifications below?
Ram Working Pressure = 2 bars
Ram ID = 100 mm.
Ram Stroke = 1,000 mm.
Homework Statement
An electron is at rest in an oscillating magnetic field
$$ \mathbf B = B_0 cos\left( ωt \right) \hat k $$
where ##B_0## and ##ω## are constants.
What is the minimum field (##B_0##) required to force a complete flip in ##S_x##?
Homework Equations
$$H=- γ \mathbf B \cdot...
Homework Statement
A point mass m hangs at one end of a vertically hung hooke-like spring of force constant k. The other end of the spring is oscillated up and down according to ##z=a\cos(w_1t)##. By treating a as a small quantity, obtain a first-order solution to the motion of m in time...
Homework Statement
Homework Equations and the attempt at a solution[/B]
Approach: Use the solution for the damped oscillating system provided in the formula sheet. We must use the given initial conditions to find the unknown phase ##\phi## and that will give us an expression for ##x## in...
Homework Statement
A mass m1 is located on a platform with mass M. The platfrom is located on springs with total constant k such that it can swing vertically in direction x.
a) Write down the equations of motion assuming mass m1 will always be connected to the platform. Write it as x(t)
b)...
Homework Statement
The question is similar to last week’s, except that we will consider how friction may damp the oscillation with time. A block with mass m shown in the drawing is acted on by a spring with spring constant k. The block is pulled distance [x[/0] from equilibrium position (x=0)...
Homework Statement
acceleration of certain oscillating particle described by a = -x/9 determine the position of this particle when t = 3π/2
if when t=0 x=0 and v=v0
Homework Equations
dv/dt=a
The Attempt at a Solution
frankly I am not sure how to start but i have two ways in my mind(even i...
Hello!
I'd like to ask for a help about how to compute accurately functions which has very intense oscillations. My example is to estimate
I = \int_0^{\infty} \sin(x^2) dx= \int_0^{\infty}\frac{\sin(t)}{2\sqrt{t}} dt.I tried trapezoid rule over one oscillation at a time, but result is poor. My...
Homework Statement
From an original surface current ##\vec{K}=K\hat{\phi}## on a finite solenoid, I got ##\vec{B}=\mu_{0}Kf(z)\hat{k}##, for ##r<R##. Assuming that ##\vec{K}## now slowly oscillates in time such as: ##\vec{K(t)}=K_{0}\cos\left(\omega t\right)\hat{\phi}##, so that I still can use...
Homework Statement
A mass m attached to a spring of spring constant k emits sound at frequency f, detected by a collinear observer at distance r. If the mass has maximum velocity v_0, what is the total number of waves the observer detects in one period of oscillation?
Homework Equations...
Homework Statement
Homework EquationsThe Attempt at a Solution
C is the point of contact and G is the CM of the plank . x be the distance between G and C .Since plank always remain in contact , x=aθ
When the line joining the point of contact C with the center makes an angle θ with the...
Homework Statement
Charge -q placed in front of an infinite plane of charge density σ
To show the oscillatory motion of the charge -q
It is allowed to impinge through charged plane
Homework Equations
Electric field in front of a charged plane is σ/2ε0
The Attempt at a Solution
Force...
I've recently learned that conductors can achieve stability when placed in an alternating electric field. This is because of Lenz's law. So I was wondering if we could levitate a conductor and stabilize it, can we do the same thing with a plasma?
If we can create a magnetic cusp, but oscillate...
Homework Statement
A thin 0.50-kg ring of radius R = 0.60 m hangs vertically from a horizontal knife-edge pivot about which the ring can oscillate freely.
If the amplitude of the motion is kept small, what is the period?
Homework Equations
T = 2pi / ω
Not sure what others...
The Attempt...
Let's say I have a metallic beam that is held so that it is parallel to the ground (0 degrees). What are the factors that affect the oscillating period of this metallic beam? I release it from a specific height so that isn't a factor.
Elasticity - won't a highly elastic metallic beam have a...
Homework Statement
Homework Equations
##
u = 1/2 a x^2\\
ke = 1/2 b {\dot x }^2\\
then\\
\omega = \sqrt{\frac{a}{b}}
##
The Attempt at a Solution
##
U = \frac{2 k q ^2}{l} + \frac{k q^2}{2 l cos \frac {\theta}{2}}
##
from that it is easily seen that equilibrium position is when the...
I know that early oscillating models of the universe fail due to the second law of thermodynamics. One thing that I am unclear about is since as far as i know the laws of physics break down in a singularity can the second law of thermodynamics break down also?
When I see comments to the...
I'm sure there's an obvious answer to this, but this problem has been confusing me for some time.
Imagine there were a massive object attached to the end of a crankshaft. A force is applied to accelerate the crankshaft, causing the mass to oscillate. Assuming there is no friction, what would...