1. donglebox

    An experiment demonstrating the principle of uncertainty

    An experiment demonstrating the principle of uncertainty,Hope to be helpful, if you like. please point out any mistakes. Simulated Video Experiments of Generalized Uncertainty Principle Introduction: The following is only the author's unreviewed understanding of the “Uncertainty...
  2. J

    Uncertainty principle

    I have a basic question on the uncertainty principle. The premise for the uncertainty is that "one will not be able to determine the position of the particle more accurately than the distance between the wave crests of light". I am trying to understand what's the basis of this primary...
  3. pittsburghjoe

    What is the Uncertainty Principle telling us?

    Is it saying the power of observation/measurement of a quantum object is not enough to make it a fully 3D + 1 space-time object? If something on our scale was partially fuzzy depending on how many measurements you made (at the same time) ..would you say it was a full fledged three dimensional...
  4. avito009

    Uncertainty Principle

    "Misconception – You cannot simultaneously measure both the position and the momentum of a particle. Correct Physics – This is the wrong phrasing of Heisenberg’ s Uncertainty Principle (HUP), which actually states that the position and momentum are not simultaneously determined. This has a...
  5. S

    What is uncertainty?

    Consider a cubical shaped object. What is the uncertainty of position when I place it along a line?
  6. N

    uncertainty and relative error

    1. The problem statement, all variables and given/known data You have an object composed of an unknown material that is in the form of a cube. You use a metre rule to measure the dimensions of the object, which are found to be 2.0 cm, 2.0 cm and 2.0 cm. The rule has a resolution of 1 mm and...
  7. B

    Uncertainty Relation for generic spin-1/2 particle

    I'm using the Quantum Systems, Processes, and Information textbook for my quantum mechanics course and working on problem 4.4 below I feel like there is a shortcut to this answer that I'm missing, because I've done several pages of algebra and simplifications and I can't seem to get a form...
  8. K

    Heisenberg Uncertainty

    Write down the time-energy form of the Heisenberg Uncertainty Principle. In an experiment, a gas of atoms in an excited state emits light at a spectral line of 550 nm as the atoms decay back to the ground state. The intensity I of the emitted light is observed to decrease with time t, with I(t)...
  9. L

    Understanding the Uncertainty principle

    blue ain’t your color lyrics, 7 years lyrics Hi everybody, I was reading about the Uncertainty principle and I came across the statement: "the position-space wavefunction of a minimum-uncertainty state is a Gaussian. Indeed, because it’s a minimum-uncertainty state, its momentum-space...
  10. S

    The Meaning of the Uncertainty Principle

    I have started this thread because the phrase "uncertainty in momentum" was used in another thread. http://physicshelpforum.com/showthread.php?t=11542 Point for discussion. What does this mean? Does it mean that the (quantum) object does not have an exactly defined momentum? Or does...
  11. O

    Question About Heisenberg Uncertainty Principle

    a) (5pts) Consider a one-dimensional square well with infinitely high potential barriers at x = ±2 × 10−15m as shown in figure a. For a proton in this well use the Hiesenberg Uncertainty Principle to derive the minimum uncertainty in the momentum and then use this to obtain an estimate of the...
  12. S


    I can do the following question but I want someone to check the uncertainty. In a microwave interference experiment, P is the first order minimum away from the centre. The measured distances and their uncertainties are: S1P=42.1+/-0.5cm S2P=46.6+/-0.5cm Calculate the wavelength of the...
  13. S

    Simple question about problem about Heisenberg's Uncertainty Principle

    For the attached problem, shouldn't Δx ~ λ/sinθ be Δx ~ λ/sinθ - -λ/sinθ = 2λ/sinθ instead such that the final answer is Δx Δp_x ~ 8πħ? The problem (along with its solution) is attached.
  14. T

    Proton mass and uncertainty principle

    The quarks inside the proton are confined into a sphere of radius equal to the proton radius r_p, and according to the uncertainty principle their momentum uncertainty is then \Delta p >= \hbar / r_p. This inequality is a lower bound to the momentum. The quarks momentum should be then spread...
  15. W

    The implications of Heisenberg's Uncertainty Principle

    I've been thinking about the uncertainty principle and I'm wondering if the following situations are settled: 1) Say you have a molecule and an atom from within this molecule goes off somewheres else in our universe. Does this mean that the chemical bond is broken? 2) How far out can...
  16. Y

    Photons and the uncertainty principle

    How do photons honour the uncertainty principle. Do they always travel at precisely the same speed. If there mass is always zero, does the uncertainty principle apply to them in any way?
  17. K

    Significant Figures and Uncertainty

    1. (a) The measured values are d1 = 3.42 ± .01 m and d2 = 7.65 ± .05 m. Defining d to be d2 - d1, calculate d and its error. I know how to do the first part but not the error part. 2. Rewrite the following answers in their clearest forms, with a suitable number of significant figures. (a)...
  18. B


    If the uncertainty in the volume of a solid sphere is 6%, then the uncertainity in the surface area of the sphere is (A) 2% (B) 4% (C) 6% (D) 12%
  19. U

    measurement correction and uncertainty of temperature

    Give a measurement result by the correction and uncertainty in the calibration of the thermometer indicator! With reference thermometer are measured 135.14 ° C, with another thermometer which was calibrated with reference we got the following values: 140.15 ° C 140.14 ° C 140.13 ° C 140.12 ° C...
  20. A

    Uncertainty principle

    Hey guys. I have this kid throwing a ball with mass M and from high H. He is trying to hit a crack in the floor. I need to show that in order for the ball not to miss the crack, the minimal width of the crack (delta x) should be the expression in the red box in the pic...