for questions about design, process, data, or analysis of experiments and observations.

learn more… | top users | synonyms (2)

1
vote
2answers
52 views

Do bad clocks measure proper time?

It has been claimed several times e.g. here, and here, also here, or (outside PSE) there that Clocks measure proper time. Or equivalenty: proper time is just the time that would be ...
1
vote
0answers
24 views

Effect of varying distance of light source from a Light Dependant Resistor

I'm doing the experiment described here and I have a few questions regarding it. I've taken a mini-LDR hooked to a multimeter set to $\Omega $ and a $25\,\mathrm W$ Light Bulb to plot the following ...
0
votes
1answer
15 views

Determine reactance force of four load cells arranged in two dimensions

I have constructed a "force plate" to reconstruct the location (x,y) of a steady state contact point force f. The system consists of four fixed compression load cells L1, L2, L3, and L4 and a thick ...
2
votes
1answer
23 views

Energy resolution of LHC Electromagnetic Calorimeter

So I am trying to get an estimate of the electromagnetic calorimeter resolution at LHCb, and I have found this online: But I have no idea of what it means. Can anyone explain what the last part ...
0
votes
0answers
10 views

Stop CO2 laser firing through holes in glass

How would you prevent a CO2 laser with interlocks used to mark glass from firing if there were holes in the glass. Usually the interlocks prevent the laser from firing unless it is pressed against ...
0
votes
3answers
97 views

If a tree falls in the forest

The question of whether or not a tree that falls in the forest makes a sound - if there is nothing or no one around to hear it - comes up frequently at my house. So, my question is: is there any way ...
0
votes
1answer
15 views

Photoelectric effect experiment: is charging time proportional to current?

I'm not really sure what tags to add to this question, but definitely this is just an introductory physics experiment. Let me refresh you first with the basics of the photoelectric effect. We all ...
2
votes
2answers
97 views

Is a Thomson's lamp physically realistic? [closed]

The Thomson's lamp is a philosophical puzzle that can be describe as follows: Consider a lamp with a toggle switch. Flicking the switch once turns the lamp on. Another flick will turn the lamp off. ...
1
vote
1answer
71 views

What is the smallest length scale ever measured?

And, by the way, what is, or are, the measured values?
2
votes
2answers
54 views

How to identify a “measuring rod”, and how to compare separated “measuring rods” with each other?

The notion of "measuring rod" has appeared in PSE here and there, and outside PSE as well. As far as I understand (and as perhaps all who refer to this notion do agree on), important constituents of ...
2
votes
3answers
65 views

What's the difference between frequency domain and time domain spectra?

If I have a mechanical oscillator and want to observe the dynamical behavior of the oscillator, is there any additional information to observe it in time domain and frequency domain? Normally, we ...
3
votes
2answers
55 views

How is the most accurate value of $G$ measured?

How do modern scientists update the measurement of $G$, the gravitational constant? Is CODATA the authority on this measurement and the experiment?
3
votes
1answer
87 views

Inexplicable Results in a Vacuum Experiment

We've been doing the following experiment in our Physics Lab course and are coming up with some strange results which we're at a loss to explain. The purpose of the experiment is to determine the ...
1
vote
0answers
18 views

Mixing liquids when applying a voltage

I'm thinking in the following experiment: A) Two (non mixable (like water and oil)) liquids are going to lie in a container, in the extremes of the container there are two electrodes, those ...
1
vote
2answers
70 views

Does a Michelson-Morley experiment uphold mass-energy equivalence and special relativity?

If there is an experiment that best supports $E=mc^2$, is it the Michelson-Morley experiment?
0
votes
0answers
10 views

How is 2D spectroscopy able to show quantum coherent transport through networks?

For wave-like (quantum coherent) energy transfer in networks (eg. propagation of excitation in photosynthetic protein complexes of algae or FMO complex in plants) 2D electronic (photon echo?) ...
0
votes
0answers
10 views

Can “uniform motion” (or “mutual rest”) be determined intrinsically, by members of Synge's “five-point curvature detector”?

In his description of a "five-point curvature detector" [1], J. L. Synge exhibits a Cayley-Menger determinant in terms of "optical distances" between five distinct participants; and he states that the ...
6
votes
1answer
103 views

How legit is this paper claiming to have observed Hawking radiation? [closed]

I recently stumbled upon this paper. In it, the author claims to have found a signature for Hawking radiation in a condensed matter system. I know that experimentalists have been trying to find ...
1
vote
2answers
61 views

What is the experiment used to actually observe the position of the electron in the H atom?

Prior to observation, the electron can be found anywhere (from inside the nucleus to the ends of the universe), but once its position is determined the answer is precise (albeit its momentum is not ...
2
votes
1answer
55 views

What is $Q_p/Q_e$ experimentally? [duplicate]

What is the experimental value of the ratio between the proton and the electron charge? Or more generally, is there a table that lists the ratio of the different nuclei charges to that of the ...
0
votes
1answer
55 views

Why can't this flying swimming pool work in practice?

I was browsing a website with funny pictures and found this one quite interesting.
4
votes
1answer
61 views

Experimental determination of speed of light

How is the speed of light measured by the most current method i.e. using lasers and atomic clocks? Alternatively, is there a better method?
1
vote
1answer
19 views

Why is the decay time of the scintilator pulse of the gamma rays longer than the decay time of neutrons?

When you discriminate between neutrons and gamma rays (using a liquid scintillator) you use the fact that the pulse due to gamma rays have a longer decay time than the pulse due to neutrons. When you ...
3
votes
1answer
25 views

Why nano indentation is used to test bulk material?

I am curious why nano indentation is used? I can understand when material size goes to micros or below, conventional hardening methods can become difficult to use. However many papers say that ...
0
votes
1answer
48 views

Resolution of experiment is lower than the detector, so how to weigh the data?

I am attempting to create an atomic model based on data from a transmission electron microscope (TEM). Basically you shoot electrons at bunch of identical molecules stuck to a grid, and look at the ...
-1
votes
0answers
17 views

Quantum camera using euclidean rotation and kabbalah

I've been playing around with procedurally generated images and the kabbalah/tesseract the last few weeks. Imagine a 3D cube sitting on top of a 2D colour wheel. One thing I noticed is that 3D ...
1
vote
0answers
30 views

A-level electromagnetism experiments? [closed]

Does anybody know any A-level experiments investigating electromagnetism that can produce good data relatively simply?
1
vote
1answer
36 views

Is there a rigorous, explicitly geometric, general characterization for whether a given clock had been “good”, or not?

In MTW, "Gravitation", there is a brief section (p. 26 and Fig. 1.9) discussing that clocks may be characterized, trial by trial, as having been "good" in the trial under consideration, or having been ...
0
votes
1answer
51 views

Simple pendulum is not so simple as it seems to be? [duplicate]

Does a simple pendulum come to stop due to the action of gravity ? Consider : No air drag, No change in place.
1
vote
2answers
37 views

Which error propagation equation to use for a function of 2 variables?

So I have been taught two formulas for error propagation: For $Z=A+B$, $\sigma_Z=\sqrt{(\sigma_A^2+\sigma_B^2)}$ and for Z=AB or Z=A/B ...
1
vote
3answers
66 views

Correction factor for standard deviation

I have conducted an experiment, from which I obtained a finite amount of values for the gravitational acceleration. The amount of values ranges from 6 up to ~150 values. I have the unbiased sample ...
0
votes
1answer
44 views

Orifice Jet Flow experiment

I am writing up a report on Orifice jet flow experiment in which I am required to find coefficient of flow velocity, $C_v$, and the Coefficient of discharge, $C_d$. There are couple of things that I ...
1
vote
3answers
147 views

How do we physically apply the operators of quantum mechanics on a particle?

What do we have to perform physically that is equivalent to applying those quantum mechanical operators on a state $|\psi\rangle$? Edit: I have removed the part I was asking regarding measurement ...
1
vote
1answer
48 views

Error in standard deviation and variance from error in data

I have a set of datapoints $x_i$ which have known upper bounds for absolute errors $\delta x_i$. (To clarify, this means each $x_i$ is actually $x_{i_0} \pm \delta x_i$). For simplicity, assume that ...
1
vote
0answers
208 views

Do these photographs depict the Higgs Field?

[PHOTO 1] Colter Dallman wrote in his paper - Space, Density, Relativity and Higgs Field Occupancy - (available online): ...
7
votes
1answer
143 views

Is it THE Higgs?

Can anyone brief me, about the status of the Higgs boson discovery and verification at CERN? Specificaly is it A higgs or THE higgs? If it is A higgs, where exactly does it differ from THE higgs? ...
3
votes
2answers
95 views

Is a wave packet physically realizable as a Fourier series?

In QM a wave packet is modeled as an infinite, or almost infinite, Fourier series, and the Fourier transform provides a transformation between momentum space and position space. To what extent is ...
0
votes
1answer
40 views

2 vacuum pumps in parallel

I have a problem with a vacuum pump that cannot generate enough vacuum to grip an uneven item. There is a spare vacuum pump in parallel which I will turn on and run at the same time to try and get ...
1
vote
1answer
65 views

Is it possible to use “negative sound waves” to “cancel out” a sound to create silence?

I saw youtube videos that claimed to do this, although I'm quite certain the videos just excluded sound and lied. However, I am wondering if the physics of this is actually possible - to create a ...
0
votes
1answer
62 views

What is logical way to calculate percentage error?

I wish to know logic behind percentage error formula. Say, $A$ is measured or calculated quantity, $B$ is theoretical or known or benchmark quantity. Then, what should be the formula for percentage ...
2
votes
0answers
61 views

Did these scientists actually detect dark matter?

I came across an article in The Guardian (definitely not the best source for science, but that's why I'm asking this question) that said that a team of scientists may have detected dark matter ...
1
vote
0answers
32 views

Scintillator Length Calculations

This is sorta homeworkish, yet it still relates to my understanding of the physics behind it as well. Does anyone know how you determine t_98 (aka the length to contain 98% of the energy) for a ...
6
votes
2answers
604 views

How is antimatter made?

How is antimatter made in laboratory? Can anyone explain, at the particle level, specifically how anti-protons and anti-electrons are made?
3
votes
0answers
38 views

How could we find preons?

If I understand correctly, scientists were able to find strong evidence for the existence of quarks by using deep inelastic scattering. If quarks (hypothetically) are composed of preons, could we use ...
2
votes
1answer
59 views

Stimulated emission in Nd:silica glass, energy levels broadening and lasers

It is known that due to absence of uniform crystalline structure in Nd-doped glasses (comparing to Nd:YAG and Nd:YVO4 crystals) energy levels of Nd+ are significantly broadened. This means that we ...
1
vote
1answer
34 views

Reason behind the train remaining intact to the Train track

I was wondering why trains moving at such hard speeds remain intact to the railway track even while turning. Is it because of friction ?
4
votes
2answers
44 views

Does measuring the air temperature near a 21 lane asphalt highway impact measurements?

The official temperature in Sydney is measured at the Sydney Observatory. This is located near the city side of the Sydney Harbour Bridge - which is a major highway. My question is Does ...
19
votes
3answers
906 views

Has the gravitational interaction of antimatter ever been examined experimentally?

I know that the gravitational interaction of antimatter is expected to be the same as normal matter. But my question is, has it ever been experimentally validated? I think it would not be a trivial ...
0
votes
1answer
117 views

Outcome from this experiment with solid hydrogen?

Let's say that we have two solid hydrogen blocks (or at least two solid hydrogen lattices) in a vacuum. Both blocks have perfectly smooth surfaces which are later put together. Before putting blocks ...
1
vote
1answer
83 views

Moment of inertia from torque and angular acceleration measurements

I tried to calculate the moment of inertia of a quadcopter along its roll axis using two different methods and the results do not match. Method 1: measuring the period of a bifilar pendulum, I obtain ...