Experiment Definition and 1000 Threads

  1. Entropix

    I Hydrogen balloon experiment -- How high can it rise?

    If we launch a hydrogen balloon from the Earth surface (let's say it has a 2 meter radius) and assuming it's strong enough so it doesn't pop/disintegrate (it's made out of carbon nano-tubes). Where this balloon will stop? I'm more interested in the exact altitude it reaches or if it will keep...
  2. Salmone

    How is an autocorrelation function computed? (Dynamic Light Scattering)

    In an experiment of Dynamic Light Scattering, how is an autocorrelation like the one in the image computed? Mathematically a correlation function can be written as ##G(\tau)=\langle I(t)I(t+\tau) \rangle##, in an experiment like the one I mentioned the scattered intensity light is collected by...
  3. M

    Instrumentation Amplifier for Wheatstone Bridge Output

    I am going to do some experiment on mechanical mechanism , studying stresses Thing that in my mind Arduino Strain gauge Instrumentation amplifier I want to know that which Instrumentation amplifier i should use to get good output voltage from wheatstone bridge circuit and also easy to use...
  4. new_scientist

    I Is the energy destroyed in this experiment?

    Suppose you stand on a spherical permanent magnet in space and you hold an iron ball in your hand, you can neglect the gravity force by this magnet mass. You stand and throw the iron ball upwards with some kinetic energy, the ball will eventually stops at some height because it is attracted by...
  5. Q

    Physics IA: Distance B/w Pendulum & Alum. Block, Finding Damping Coefficient

    TL;DR Summary: I am doing an experiment for my Physics IA and don't know the theory behind it I am working on a Physics experiment for my school where I vary the distance between a simple pendulum and an aluminium block, and get the damping coefficient for each distance. Below are the images...
  6. M

    What are some fun permanent magnet experiments for kids?

    Howdy. My kids and I like to experiment with things, we're looking to play around with some permanent magnet experiments and when I googled a question it brought me here, so I figured, heck, might be able to get my questions answered as well :)
  7. Grelbr42

    I The Potential of Back-to-Back Photons: an Experiment

    In some cases, photons can be produced in "back to back" (BTB) conditions. For example, electron-positron annihilation produces two photons, each at 0.511 MeV, with equal and opposite momentum. Or pretty close, up to the original velocities of the electron and positron. Start with a source of...
  8. hyksos

    I Exploring the Casimir Effect: The Archimedes Experiment

    Vacuum energy is predicted by Quantum Field Theory, and also independently corroborated by recent observations in cosmology involving accelerated expansion. More corroboration occurs in superconducting cuprates exhibiting quantum criticality, and in the Casimir effect The island of Sardinia...
  9. S

    Experiment about diode related to temperature and potential difference

    (a) I know some of the apparatus needed for the experiment, such as DC power supply, ammeter, voltmeter, maybe rheostat. But I don't know how to change the temperature of diode. What is the correct and safe way to change the temperature of diode? Thanks
  10. B

    I Faraday's Nested Sphere Experiment

    Hi there! I have a question about the Faraday's Nested Sphere Experiment, please see the attached pdf. I wonder why equation (1) and the electric field's equation ( coming after (1) ) consider only the charge Q. Why there aren't charge -Q in the equation? Ps. I'm thinking about point charges...
  11. sbrothy

    I Classic 'Double-Slit' Experiment Using Time Instead of Space

    (Not sure about the prefix. Choose intermediate to be sure.) This article Physicists Recreate Classic 'Double-Slit' Experiment Using Time Instead of Space has it's basis in this paper: Double-slit time diffraction at optical frequencies It certainly sounds intriguing but is there actually...
  12. Astronuc

    I Experiment finds gluon mass in the proton (?)

    Article published at Phys.org - Experiment finds gluon mass in the proton https://phys.org/news/2023-03-gluon-mass-proton.html An interesting diagram accompanies the article. Article in Nature (requires subscription or purchase, but one can read the abstract)...
  13. Addez123

    B What is causing destructive interference in double slit experiment?

    When you do the double slit experiment with photons or electrons you get a wave pattern. At certain points no electrons are detected. This is said to be caused by destructive interference. Destructive interference of what? If we shoot single electrons, one at a time, from where is this...
  14. K

    B Simple yet effective way to reliably control the DC Motor speed?

    As a part of our physics high-school self-study, we are making a stroboscope. We have a small 5-V DC motor that powers the strobe disk. It works as expected, but, clearly, the motor makes the disk spin at a constant speed. Is there an easy, but effective and reliable way to control its speed...
  15. K

    B Searching for Quantum Mechanics Lecture on Delayed Choice Experiment

    Hi everybody. Some years ago I came across a video on youtube where they talked about an experiment with small and large envelops, when the small ones were placed into the large ones and then it resulted in something interesting. It might have been an instance of delayed choice, but I am not...
  16. J

    I Observer effect in the Dual Slit experiment

    How detectors/observers in front of each slit works , does it somehow disturb with electron/photon? Does photon/electron must pass through detector/observer, so maybe his internal parts change final result on screen into just two lines?
  17. C

    A Two Slit Interference Experiment Variations

    Examples that have references to special two slit experiments : https://sciencedemonstrations.fas.harvard.edu/presentations/single-photon-interference https://en.wikipedia.org/wiki/Double-slit_experiment If you have an opinion on what you think the experiments tend to support and what they do...
  18. S

    I William Herschel's light experiment

    In Cosmos: A Spacetime Odyssey episode 5 Hiding in the Light, Neil Degrasse Tyson describes one of William Herschel's experiments with light in the year 1800. The episode shows Herschel's experiment as a cartoon. Herschel put two thermometers under a prism that was in the sunlight. Herschel put...
  19. C

    B A thought experiment of the relativity of light

    A light source in uniform motion emits a flash of light. A spherically symmetric wavefront propagates from a central point, the source, or the “origin” of emission. The wave front remains at c relative to the origin as measured by all observers. How fast do these origins move? Am I missing...
  20. V

    I How to rule out that the speed of light was different in the past?

    The constancy of the speed of light is a fundamental principle in modern physics, and it is supported by a wide range of current experimental evidence. There is no evidence to suggest that the speed of light was different in the past, and the idea that it could have been different is at odds...
  21. Beekeeper

    I Why Isn't My Sonoluminescence Experiment Working?

    Hi, I am working on a sonoluminescence experiment and am having trouble with it. The problem is that although I can trap a bubble, I cannot get it to glow. I am following the same procedure described by 'The Thought Emporium' and you can see a video about it here: . In a nutshell the procedure...
  22. nomadreid

    Investigating Unexpected Results in Elementary Experiment

    This concerns an elementary experiment that I (a teacher) have done with several secondary school classes, up until now with success. However, I gave the same instructions to a homeschooling student (in another country , so I couldn’t actually directly oversee the experiment), and the...
  23. haha0p1

    Doing experiment to find the authenticity of Archimedes' law

    I have solved the question like this: Since Volume=Upthrust We need to find the upthrust and the volume V. To find the volume, we will submerge the block in the water and find the difference. To find the upthrust F, we will subtract the weight (finding the weight usinf newton-meter) from the...
  24. PeterDonis

    A Can the double slit experiment distinguish between QM interpretations?

    This paper claims that the double slit experiment can be used to distinguish between QM interpretations: https://arxiv.org/abs/2301.02641 IMO, the paper goes astray right at the start, when it points out that time is a parameter in the Schrodinger equation, not an operator, so that equation...
  25. N

    Particle Maxwell's demon full experiment description

    Hey! Does anyone have the large/full description of Maxwell's demon thought experiment? I've read it on Wikipedia, but I was wondering if someone knows a better source I can reach legally. Thanks.
  26. Spathi

    I Experiment with gamers, random numbers and entanglement

    https://www.wired.com/story/this-random-video-game-powers-quantum-entanglement-experiments/ I don't understand the principle of this experiment. The gamers produced random numbers, and what was done with these numbers then? Was the value like <S> in CHSH inequalities computed, and was it...
  27. N

    Weird barometric formula experiment results in Excel

    Hi, as I know the barometric formula is an exponential equation, but when I did the experiment with a barometer at different heights and inserted these results in Excel for curve fitting, it showed a weird thing, I think. So exponential equation did show that R^2=0.942 and the second-degree...
  28. physicsclaus

    How to calculate gating time from the rate of the random coincidence?

    Hello everyone, I am now doing experiment related to quantum erasure. After plotting the correlation measurement with and without blocking one of the polarization from the SPDC source (say, V polarization), I do not know how to work further on the gating time from the rate of the random...
  29. S

    I Query on use of prism in delayed choice quantum eraser experiment

    Hi. I’ve seen a number of schematic diagrams for the Delayed Choice Quantum Eraser experiment. Some include a prism to make the two idler photon paths diverge. However, the prism is shown refracting the ‘idler rays’ in a way which contravenes Snell’s law. E.g. see prism marked ‘PS’ (not the...
  30. K

    B Eddington Exp vs Newton: Comparing Starlight Deflection

    The Eddington Experiment famously confirmed GR by showing, as Einstein had predicted, a deflection of starlight by the Sun that was double the deflection expected by Newtonian gravity. I don't understand where Einstein's 2x number came from. I make the following assumptions: 1. That a ray of...
  31. R

    B Does the bomb experiment do a measurement?

    In short, the Elitzur–Vaidman bomb experiment consists of a Mach–Zehnder interferometer, where a bomb is placed in one of the paths (I used the wikipedia description https://en.wikipedia.org/wiki/Elitzur%E2%80%93Vaidman_bomb_tester, and Sabine Hossenfelder's video: ) The bomb can be live or a...
  32. Rezex124

    Experiment - how temperature changes along a tube, using heaters

    TL;DR Summary: Help needed with plotting heat maps, using data we gathered in an experiment. Hello, so I'm having problems with analysing data, which we gathered from an experiment we did in class. This is meant as a type of non-guided experiments class, where we are just given an initial...
  33. Viona

    I Compton scattering experiment

    I was reading about Compton scattering. I have a question I did not find an answer for it in the book (Concepts of Modern Physics-Sixth Edition-Arthur Beiser) or in the internet search. My question is: Is the incident X-ray beam, with the original wavelength, detected at different scattering...
  34. Mr Fallspring

    I Double-Slit Experiment: Does rate of photon emission matter?

    Hi there! High school physics teacher hoping to pick the brains of people who know more than I do here. I'm curious whether the rate of photon emission has any noticeable effect on the diffraction pattern generated by the double-slit experiment. To be clear: I understand a diffraction pattern...
  35. J

    I Double Slit Experiment Mathematics

    Electrons are shot thru two slits separated by a distance s at a screen a distance ##z_0## away. The wave function for the particles is proportional to ## e^{ik \sqrt{(x-s/2)^2+z_0^2}} +e^{ik \sqrt{(x+s/2)^2+z_0^2}}## Taking the first one, we can manipulate the square root algebraically...
  36. G

    A The experiment of Kim et al. (1999) (with small modification)

    Modification specifications: Variation 1. Placement of horizontal polarizer after BSa. Placement of vertical polarizer after BSb. Variation 2. Placement of horizontal polarizer after Ma. Placement of vertical polarizer after Mb. Question1: Is it safe to assume, that this modification...
  37. D

    B Non-parallel double slit experiment

    Is it possible to tell which slit some of the light went through when the slits aren’t parallel (green & red boxes in option 3)? I used a Bahtinov mask to cover the aperture of my 600mm f/9 lens while observing the star Polaris. Various open slits were tested while others were covered with...
  38. T

    I Double-slit experiment, determining which slit an electron passed thru

    I was reading Feynman's lecture on the double-slit experiment, the attempts to determine which slit an electron passes through. https://www.feynmanlectures.caltech.edu/III_01.html#Ch1-S6 And the key part is when Feynman says, "Then a terrible thing happens.", about the low optical resolutions...
  39. A

    Second bright fringe in Young's Experiment

    In Young's double split experiment, a narrow beam of light of wavelength ##589nm## passes through two slits to form an interference pattern on a screen which is a perpendicular distance of ##D## metres away from the slits. The slit separation is ##0.2mm## and the second bright fringe is ##6mm##...
  40. Y Y Kim

    I What is the meaning of 'CP violation' in the Cronin and Fitch experiment?

    Below are the statements in the "David Griffiths, Introduction to Elementary Particles 2nd Edition, 147~148 p.": Evidently, the long-lived neutral kaon is not a perfect eigenstate of CP after all, but contains a small admixture of K1. The coefficient epsilon is a measure of nature's departure...
  41. Ahmed1029

    I Michelson–Morley experiment and the velocity of the ether wind

    How was it justified before conducting the MICHELSON–MORLEY experiment to assume that the sun was at rest with respect to the ether? Also, was the ether assumed to have the same velocity with respect to the Earth throughout space at one instant in time, or like wind, with different velocities at...
  42. Christian Thom

    I Double-slit experiment with momentum entangled pair of photons

    In Kaur, M., Singh, M. Quantum double-double-slit experiment with momentum entangled photons. Sci Rep 10, 11427 (2020). https://doi.org/10.1038/s41598-020-68181-1 and in C. K. Hong and T. G. Noh, "Two-photon double-slit interference experiment," J. Opt. Soc. Am. B 15, 1192-1197 (1998) it is...
  43. D

    I Magnus Effect experiment problem

    Hello, I'm currently doing a school essay on the Magnus Effect, but I'm having a problem regarding a contradiction between my measurements and calculations. The experiment consists of letting go of rolled A4 paper cylinders on top of a ramp set on a table so that when the cylinder rolls down...
  44. Filip Larsen

    B Weak Equivalence Principle Confirmed by MICROSCOPE Satellite to 10^-15

    https://arstechnica.com/science/2022/09/einstein-wins-again-space-satellite-confirms-weak-equivalence-principle/ See also http://dx.doi.org/10.1103/PhysRevLett.129.121102 (limited access)
  45. J

    What are Joe's interests and goals as a new member and citizen scientist?

    My name is Joe, I'm 36 years old and currently between work. I live in The city of Erie, Pennsylvania. My interests are in the phields of electricity, physics, chemistry, and all engineering principles related. As I am only a high school graduate with no formal training, my education is self...
  46. entropy1

    I Does the photon in a double slit experiment create many worlds?

    I can't find the anwer on this anywhere, so I hope I may ask it here. My question: In a standard double slit experiment, according to the Many Worlds Interpretation, does the photon create different worlds with different impact locations of the photon? So, without measuring which way...
  47. V

    I Michelson-Morley: Errors in Calculations?

    I would like to know the opinions on the paper that I saw about Michelson-Morley experiment. Michelson-Morley experiment was done in 1887 and had an impact on the future direction of physics. It is taught in schools as an experiment that proves the non-existence of the aether and proves the...
  48. Marilyn67

    I Young's slit experiment with single photons

    Hello, I have a little problem understanding Young's slit experiment with single photons : I have understood for a long time that each photon impact on the screen corresponds to a photon sent by the source, and that, if we don't try to find out by which path the photon has passed, of course...
Back
Top