Uncertainty Definition and 1000 Threads

I am trying to figure out how to refer to two overlapping uncertainty results. I have to write a conclusion and I find it difficult to explain. Even now it may seem unclear as to what I am referring to so I will provide an example. This is directly from my conclusion. 'The 72 rated golf ball...

I'm a bit confused about how the uncertainty principle allows for the spontaneous creation and annihilation of virtual particle pairs. I can understand that energy conservation can be violated for a very short time as per delta_e*delta_t > h_bar/2. However, when the virtual particle pair...

Homework Statement In Bohr model of the hydrogen atom, the max. kinetic energy that an electron can have is around 13.6 eV, as it would otherwise not be confined to the atom. Uncertainty Principle: ΔxΔy ≥ h/2π a) Find the max. momentum of such confined electron. b) Use Uncertainty Principle...

it should be called as unpredictability rather than uncertainty principle because the event is certain but we cannot predict it.

I'm working on a few problems involving the Heisenberg Uncertainty Principle and I'm a little confused as to how the equation works and what to plug into the equation. The equation I'm using is: (delta(x)*m*delta(v) = h/(4pi). In one of the problems I'm working on, I'm given the mass of a...

how Energy time uncertainty principle account for the broadening of a level? thanks in advance

Homework Statement Determine the energy uncertainty \Delta E = \sqrt{<E^2> - <E>^2} for a particle described by a wave function \Psi (x) = c_1 \psi (x)_1 + c_2 \psi (x)_2 where \psi_1 and \psi_2 are different (orthonormal) energy eigenstates with eigenvalues E_1 and E_2. Homework...

hi i am looking for the correct equation, that gives me the linewidth by knowing the time of the emission process. so far, i found in the internet: Δf=1/(Δt), Δf=1/(4πΔt) and Δf=1/(2Δt) can you tell me, when i have to use which of these equations and maybe whether you think that...

Let me first start off by saying that I am somewhat new to physics and it's understanding. But I was looking over the Hiesenberg Uncertainty Princple and a thought occurred to me. The Heisenberg Unvertainty Principle states "More precisely the position is determined, the less precise the...

Homework Statement Show that, if [H,A] = 0 and dA/dt = 0, then <&Delta;A> is constant in time. Homework Equations d<A>/dt = <i/ℏ[H,A] + dA/dt> The Attempt at a Solution I am trying to use the above equation to show that d<&Delta;A>/dt is 0, and I can get to d&Delta;A/dt = 0, but I...

Homework Statement Find the acceleration of gravity. Using the trendline equation of Force v. hanging mass, find the RMS uncertainty for the force. Trend line equation: y = 9.8968x - 0.0342 R² = 0.9493 Data Values: Hanging mass is the first number. Force is the second number...

I'm asked to show that in the ground state, a particle trapped in a potential well approximately equal to its lowest allowed energy. I know the expression for the energy is h^2/8mL^2 for a finite well, and ΔEΔt~h/2π. But I'm at a loss as to how I'm supposed to even begin to start this...

Homework Statement The linewidth of a certain fluorescing dye molecule is 60nm and the peak emission wavelength is 600nm. The lifetime of the dye molecule in the excited state is 1ns. Determine whether the linewidth of the emission is a result of the uncertainty principle. (it may be helpful...

Hello I know this topic must have been done to death already, but i can't seem to find a satisfying answer. As the title suggests, my question is, what experiment proves that the uncertainty principle is not just a result of our flawed measuring techniques? From what i understand, when we...

Homework Statement Use the uncertainty principle to estimate the ground state energy of a particle of mass "m" is moving in a linear potential given by V(x) = ∞ for x≤ 0 V(x) = αx for x ≥ 0 Homework Equations ΔxΔp ≥ h/2 The Attempt at a Solution I've looked at a similar problem...

What's the kinetic energy uncertainty for gaussian wave packet ψ(x)=((α/pi)^(1/4))exp(-αx^2/2)?

Homework Statement An electron is confined within a region of atomic dimensions on the order to 10-10 m. Compute the uncertainty in its momentum. Homework Equations N/A The Attempt at a Solution I know this problem involves a simple application of Heisenberg's uncertainty...

Homework Statement I am having trouble calculating uncertainty when a number is added to a value with uncertainty. M = 350g a = 0.624 \pm 0.001 µk = 0.07 g = 9.80 m/s2 Homework Equations T = M*a + µk*M*g The Attempt at a Solution T = (350g)*(0.624 m/s2) +...

Homework Statement m 7.29 7.31 7.3 7.31 7.27 7.28 7.31 7.29 7.28 7.27 7.26 7.3 87.47 mean 7.289166667 using the values in the table calculate the uncertainties on the mean values of m The Attempt at a Solution I thought finding the difference between the...

Heisenberg's uncertainty principle only seems to have implications for our understanding of the body of knowledge produced by science, not reality itself. The uncertainty comes from the inability to make two separate measurements, since each measurement will disturb the system and change the...

Homework Statement Using Heisenberg's uncertainty principle, calculate the uncertainty in the position of a proton moving at a speed of (5.00±0.01) x 10^4 m/s. Homework Equations Δx\geq \frac{h}{4mΔv\pi} The Attempt at a Solution x\geq (6.626*10^-34)/(4pi(1.6726*10^-24)(5±0.01 *...

Homework Statement If I measure A=50, with a minimum value of 48, and a maximum value of 51, and measure B=100, with a minimum value of 92, and a maximum value of 115, and I add the two (C=A+B) together, what is the resulting minimum and maximum value of C? Homework Equations If A...

I'm trying to understand the Heisenberg Uncertainty Principle, as it relates to experimental measurements, because it's kind of confusing me. We just learned the derivations for it in my QM class -- basically it's two standard deviations multiplied together (corresponding to measurements of...

Can someone point me in the right direction or give me a rundown on how to use the least squares method in calculating the uncertainty in a gradient of a graph? We have been given a theoretical experiment with data and so on supplied and we need to find the uncertainty of the graph we have...

Homework Statement If an electronic scale reads 502.4 g, what is the absolute uncertainty in the mass reading. Homework Equations Not sure The Attempt at a Solution Not a clue, it seems that there isn't enough information given. How am I supposed to figure out the absolute...

A simple pendulum is used to measure the acceleration of gravity using T=2pi(sqrt(L/g)) . The period T was measured to be 1.24 ± 0.02 s and the length L to be 0.381 ± 0.002 m. What is the resulting value for g with its absolute and relative uncertainty? So the first thing I did was to isolate...

Hello, I'm trying to figure out a way to calculate a suitable uncertainty value for the accuracy of a human measuring timing values during an experiment. The experiment was designed to determine the frictional force acting on a trolley as it is pulled along by a string attached to a...

The uncertainty principle says that you can't simultaneously measure position and momentum with arbitrary precision. So you can measure one at a time t1 and the other at a time t2 with t2 > t1, thus not measuring both simultaneously, but relativity tell us that there exists a frame of reference...

Please check if my solutions are correct or if I am totally wrong. Thank you! 1. Homework Statement [/b] In an experiment to measure the density of a steel ball. The diameter of the ball is d= 1.76 +- 0.02 cm and the mass to be m= 22 +- 1g. (include error calculations and report values with...

Hi, I was watching Through the Wormhole two weeks ago (I think it was a re-run), and they were talking about the uncertainty principle, and how it was impossible to prove due to the change in momentum of a particle when hit with an observation device, such as light. I think the guy was using...

Hi- I apologize if this has been covered elsewhere, but after much searching with no luck... I am taking a lab class, the first in a while, and am using Matlab's Curve Fitting tool to fit data to exponential curves. My question is how to translate (if possible) the "goodness of fit"...

Homework Statement What is the approximate uncertainty in the area of a circle of radius 5.3 * 104 cm? Express your answer using one significant figure. Homework Equations A = pi*r2 The Attempt at a Solution Using the given radius, I found the area to be 8.8 * 109 cm2. And since...

Homework Statement The centripetal force is given by F= (mv2) / r. If the mass is measured to be 2.8 +/- 0.1 kg, the velocity is 14 +/- 2 ms^-1, and the radius 8.0 +/- 0.2 m, find the force on the mass, including the uncertainty. Homework Equations F= (mv2) / r The Attempt at a...

I understood the Delayed Eraser experiment, and the Eraser experiment and the basic double slit experiment. And all I can conclude is, why? Why is there such a necessity? I now understand that it's most probably impossible to learn the 2 properties at the same time but I don't see any...

If Uncertainty Principle is a result of 'fiddling' of an apparatus with what is being observed (for example light particle/wave of a detector fiddling with particles/waves being observed), then wouldn't uncertainty principle cease to apply if in the future a 'smaller' or 'less interfering'...

A while back, one of my undergraduate physics professors gave an argument for why the uncertainty in a function or quantity F is given by \Delta F = \sqrt{^{N}_{i-1}\sum(\frac{\partial F}{\partial x_{i}})^{2}(\Delta x_{i})^{2}} He argued to think of a right triangle and think of...

Question on "estimated uncertainty" and significant digits Homework Statement The value is 136.52480, and the "estimated uncertainty" is 2. How many digits should be included as significant? Homework Equations Not sure whether estimated uncertainty refers to a 1σ (68.26%) confidence...

I've been exposed to two different interpretations of the uncertainty principle. 1) If an electron is in a certain state, a measurement of its position will yield a definite result. However, if after the measurement the electron could be returned to the same state, then a repeated measurement...

Homework Statement Finding uncertainty in magnetic field strength. N=2, i=1.00\pm0.005 A, R=0.1 m, \tan \theta=0.49\pm0.008 Homework Equations The equation B_{coil}=\frac{\mu_0 N i}{2 R \tan \theta} The Attempt at a Solution I am assuming that the radius R and number of turns N are exact. I...

Homework Statement Ok, I don't have a problem with the question, but what I believe to be an empty set variable is used which I have not covered in a course before. My problem is that I do not know the relevance of an empty set in part b) of the equation. Homework Equations The equation and...

Hi all, I have a question regarding least-squares, and I'm certain I can't be the first one to encounter it, but I've had no luck searching the literature for a solution. Here it is: Say we have a non-linear least-squares optimisation problem. We have data points y_i and a model y(x_i;{\bf...

Hi all, I am sure this is a quite simple question but I just can't figure it out, any helps would be greatly appreciated. If a particle stay in a state in a very short time, then by energy time uncertainty relation, it's energy must has a great uncertainty. Also because of energy is propotion...

Hi - I'm new here - I'm just writing a paper based on an acoustical analysis of a rock/pop performance venue in a college I work at, and I'm up to my uncertainties section. I've read up on uncertainties, and feel confident in working out uncertainties for simple additions, multiplications...

Homework Statement As you eat your way through a bag of chocolate chip cookies, you observe that each cookie is a circular disk with a diameter of 8.50+-0.02cm and a thickness of 0.050+-0.005cm. Homework Equations a. Find the average volume of of a cookie and the uncertainty in the...

couple of questions a) the operators not commuting would also be true of position and momentum operators in classical mechanics (x d/dx -d/dx x) f(x) so the non-commutation does not inherently constitute a proof for the uncertainty principle, or do you just not care about the uncertainty at...

I was recently thinking about the Heisenberg Uncertainty Principle which states that we can not know a subatomic particle's position and momentum at any instant. We can know one or the other measure but not both at the same time. The more we know about one, the less we know about the other...

Here's how I understand it: The light of a shorter wavelength disturbs the momentum of the electron, but shows the electron's position. Why doesn't the light of a longer wavelength disturb the momentum of the electron?

I've come across an apparent paradox in elementary quantum mechanics, and after a little Googling, haven't found a reference to it. Here goes, The 1-D infinite square well is a classic problem in introductory QM. We find that the position-space eigenfunctions of the Hamiltonian (the "allowed...

You are no doubt familiar with Heisenberg's uncertainty principle, putting a limit on the accuracy with which we can measure a particle's position and momentum, \Delta x \Delta p \geq \hbar/2 On my course I was shown the derivation, it popped out of a few lines of mathematics involving the...

While reading Feynman's 6 Easy Pieces, I see he talks about bouncing photons off of the electrons that are passing through two slits. According to Feynman, when a photon strikes an electron near one of the slits, it bounces (sometimes back at the observer) and registered as a sharp point of...