I have a measurement with uncertainties for two years. Say
Year 1 Rain : 100mm(80-120mm)
Year 2 Rain : 120mm(103-131mm).
Now I get the percentage change in rain in Year 2 w.r.t Year 1 as 20%. Is there a way to get the uncertainty associated with this percentage change?
My question is: is the resolving power of an array of radio telescopes a quantum or a classical effect? The increase in resolving power of a single telescope, as aperture size increases, is easy to explain in terms of Heisenberg's uncertainty principle. But when we go an array of telescopes are...
1. Homework Statement
For the ground state of a particle moving freely in a one-dimensional box 0≤x≤L with rigid reflecting end points, the uncertainity product (Δx)(Δp) is
(A) h/2
(B) h√2
(C) >h/2
(D) h/√3
2. Homework Equations
The uncertainity principle says that -
(Δx)(Δp) ≥ ħ/2
Ground...
I have seen that the more a particle has a high energy, i.e ##E##, the more its lifetime is short, respecting so the uncertainty principle.
But by the definition of this uncertainty principle :
##E\,\Delta t \geq \dfrac{\hbar}{2}##, I can write :
##\Delta t \geq \dfrac{\hbar}{2E}##, then...
If I understand it correctly, a particle doesn't have a definite momentum and a definite position, but is in a superposition of multiple positions and momenta. And when we measure either of the two quantities, say, position, the wavefunction collapses to tell us where the particle is. Now when...
If we have a particle, say, an electron and we shoot it straight through an empty box. This box is surrounded by light sources on its two sides:
So, if you consider the above cube, if we shoot a particle in a straight line such that it crosses the face ABEF and it crosses the face HGDC through...
Heisenberg's uncertainty relation says:
$$\Delta x \Delta p \ge \hbar$$
If we assume a massless quantum object then we have the relationship ##\Delta E = c\Delta p## so that the above uncertainty relationship becomes
$$\Delta E \ge \frac{\hbar c}{\Delta x}.\tag{1}$$
I understand that if we have...
Hi all,
Yet another question: if the universe is finite, then linear momentum should be quantized (I assume in a similar manner to an infinite potential well since there are boundary conditions). My question is, then, if one computes a value for ##\Delta p## (momentum variance), is the variance...
Hello.
What I know about the Van der Waals force is that it comes from an instantaneous electronic cloud flucutation of the netural atom. This instantaneous electric dipole of the atom attracts electrons in nearby neutral atoms so other electric dipoles are induced on those atoms. As a result...
Imagine a spatial frame of reference attached to a point-like particle. It has x=0 since it is at the origin and p=0 since it is at rest. Having definite position and momentum is normally considered a violation of the uncertainty principle. How would you resolve this paradox?
1. Position frames...
When looking at a night light with almost closed eyes, I notice that the light becomes a vertical line. When tilting my head 90 degrees, the line becomes horizontal.
Can this be explained by Heisenberg's Uncertainty principle?
This question has been asked in another thread : "Squinting at...
1. Homework Statement
A horizontal beam of laser light of wavelength 474 nm passes through a narrow slit that has width 5.80×10−2 mm . The intensity of the light is measured on a vertical screen that is 2.40 m from the slit.
Use the result of part A to estimate the width of the central...
1. Homework Statement
See Image
The bit about Spectral lines, I couldn't explain why
2. Homework Equations
ΔEΔt≈h
3. The Attempt at a Solution
I expected the histogram to peak at the given mass in question and to have a width of about 0.08 MeV calculated as ΔE from the Energy-time...
what can be the uncertainty of the frequency that humans can hear ?
I'm aware that there are many ways,but i tried google-ing to find them but i couldnt.
if you could help me it would be great.
Dear PF Forum,
Determinism.
1. Is there determinism?
2. Because we can't measure the electron position, it doesn't mean there's no determinism?
Heisenberg uncertainity principle states, per wiki:
But because we can't measure it, it doesn't mean that the universe itself is indeterministic...
For an electron can I not do the following to determine both the position and momentum? I take a screen with a small hole and I eventually make the hole smaller and smaller. Cathode rays emitted will hence get diffracted after passing through the hole making momentum more and more uncertain...
I was reading the Feynman Lectures awhile back and I remember reading something he said about the Uncertainty Principle and it seemed slightly odd to me. I don't remember the exact quote and combing through some of the lectures online I can't quite find it. I've heard it more than once from...
The principle states it is impossible to 'simultaneously' know the position and momentum(velocity)of an object. Position is something that can be noted at a particular instant, as from a photograph whereas velocity is something that can only be measured over a period of time,as from a movie. The...