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

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2
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1answer
108 views

What are the theoretical prerequisites for experimental work with SEM and TEM? [closed]

What level of knowledge and in what areas would be required to perform experimental work with an SEM (Scanning Electron Microscope) and a TEM (Transmission Electron Microscope) respectively? E.g. ...
4
votes
3answers
537 views

Newton's First Law of Motion; Empirical Aspects

Newton's first law states that in an inertial frame, a body at rest continues to be at rest, and a body in constant rectilinear motion continues its motion, unless an external force is applied upon ...
1
vote
1answer
297 views

How to interpret temporal coherence in Young's double slit experiment with single photons?

I have a problem with understanding what is the role of coherence in such experiment. Taking the Dirac's statement that photon interferes only with itself, it's fairly understandable, that single ...
2
votes
0answers
1k views

How the value of permitivity of free space is determined?

when electric charges are placed on the medium then force of interaction between them decreases. We say this factor permitivity of the medium. The force of interaction between the charges is max if ...
25
votes
1answer
779 views

Best current bounds on nonconservation of momentum?

It's not straightforward to test conservation of momentum experimentally, and many experiments that seem like tests really aren't. For example, in a Newtonian system of identical particles that ...
3
votes
1answer
468 views

Easy to do experiments that clearly show outstanding properties of graphene

By chance we received for free some monolayer graphene sheets (20 cm x 20 cm) and mixed coper-graphene wires at our University. I would like to prepare some very easy to do experiments for the ...
18
votes
5answers
1k views

How can I determine whether the mass of an object is evenly distributed?

How can I determine whether the mass of an object is evenly distributed without doing any permanent damage? Suppose I got all the typical lab equipment. I guess I can calculate its center of mass and ...
1
vote
1answer
81 views

Interpreting the results

I have preformed the muon lifetime experiment at my uni's lab, and got the data. It's text file with 8190 numbers. My TDC unit was set so that the time gates were at 10 $\mu s$, and it has 8192 ...
2
votes
1answer
1k views

How does the speed of a DC motor depend on the size of the coil?

I have to build a simple electric motor by attaching a magnet to a battery, extending the terminals of the battery (with stiff wires so they could act as supports), and placing a coil of wire on top ...
5
votes
2answers
1k views

Optics alignment of a confocal scanning microscope

I am facing a challenge in my project regarding optical alignment. See the figure: The challenge is with the vertical optical system alignment. I considered placing a mirror and check back if the ...
2
votes
4answers
10k views

How can we detect X-rays?

I know that X-rays can be detected by various ways, like ionizing of air particles. Is there a way to detect X-rays,which are photons, by detecting? Can something absorb the energy of the X-rays and ...
9
votes
2answers
992 views

Mechanical Equivalent of Heat

Recently I have been looking up James Joule's experiment regarding the mechanical equivalent of heat. After viewing some drawings of the apparatus, I assumed that the lines holding the weights would ...
3
votes
0answers
183 views

List of cross sections?

Sometimes I need to look up a certain cross section, say the inclusive Z production cross section at $\sqrt{s}$ = 7 TeV. Is there a place where 'all the' cross sections are tabulated (...
4
votes
2answers
214 views

Cosmological triangle with PLANCK results

Is there an updated version of the cosmological triangle with recent PLANCK results included?
2
votes
1answer
553 views

Experiment to find Ammeter Resistance [closed]

I've been studying experimental electrodynamics and I needed to describe an experiment to find the resistance of an ammeter if I just have the ammeter together with one voltmeter and a protection ...
30
votes
1answer
1k views

Status of experimental searches for tachyons?

Now that the dust has settled on the 2011 superluminal neutrino debacle at OPERA, I'm interested in understanding the current status of experimental searches for neutrinos. Although the OPERA claim ...
6
votes
2answers
489 views

Concerning Scattering Intensity and Particle Concentration

I am trying to determine what governs my sensor output. I have an optical sensor that emits infrared radiation on a sample volume and gives me a voltage output from the scattering of (1 to 10 micron) ...
10
votes
1answer
561 views

How the inverse square law in electrodynamics is related to photon mass?

I have read somewhere that one of the tests of the inverse square law is to assume nonzero mass for photon and then, by finding a maximum limit for it , determine a maximum possible error in $\frac{1}...
0
votes
1answer
2k views

measuring electromagnetic induction

There is a famous law which says that a potential difference is produced across a conductor when it is exposed to a varying MF. But, how do you measure it to prove? It is quite practical. ...
0
votes
1answer
199 views

Can thought experiments qualify as actual research?

I wondered whether thought experiments actually can be substituted for actual experimentation. I understand that in some cases it might be necessary, but can it be unnecessary over thinking sometimes? ...
13
votes
4answers
914 views

Can we measure an electromagnetic field?

As far as I can check, the Aharonov-Bohm effect is not -- contrary to what is claimed in the historical paper -- a demonstration that the vector potential $A$ has an intrinsic existence in quantum ...
4
votes
1answer
221 views

How important is it, really, to clean vacuum parts?

In every lab I've seen, people are quite meticulous about cleaning parts that are to be used in ultrahigh vacuum, as well as the components of the chamber itself. The parts may be put in an ultrasonic ...
2
votes
2answers
281 views

Parabolic motion (experiment)

We performed a laboratory, performing six releases of a sphere with angles $15^\circ,30^\circ,45^\circ,60^\circ,75^\circ,40^\circ$ a parabolic movement, took five distances for each angle, the initial ...
2
votes
0answers
164 views

Robot controling pouring process from a bottle

I need to solve a problem within mechanic of fluids for a part of my thesis. Robot will pick up a bottle of beer, cola, julebrus or any other kind of beverage. And then it has to bring it to the glass ...
1
vote
1answer
32 views

Are “timed” measurements actually revealing error-distributions of the measurement apparati?

A thought experiment: Given some object moving (swinging) from left to right and back with constant velocity, imagine a camera set up to take a picture of the scene at a fixed interval so that we can ...
3
votes
1answer
4k views

What is Transverse Energy?

What is transverse energy? Why we use transverse total energy instead of energy and transverse momentum in place of Total momentum in the particle detectors?
3
votes
1answer
679 views

Planes of graphite crystal on diffraction experiments

When doing electron diffraction on graphite (a popular experiment for students at universities) always diffraction at these two planes with distances $d_1$ and $d_2$ are observed: But a plane ...
3
votes
1answer
532 views

Explain background pattern in particle tracing image

I'm trying to understand this image of a particle tracing experiment (which can be found all over the net if you google for "bubble chamber"): ( There are two things that I can't figure out: The ...
5
votes
1answer
869 views

Whistling on bottle tops

It is well known that if you blow horizontally on a bottle top it creates a sound. Pouring water to the bottle changes the pitch. I have been doing experiments on the relation between the sound's ...
0
votes
1answer
6k views

How do you find (initial) velocity using conservation of energy?

Without mass; only time, distance, and height is given. For example: For this lab, the reference level was 100cm above ground therefore the height of the object was 10cm. I determined time and ...
7
votes
2answers
687 views

How quark electric charge directly have been measured?

How quarks electric charge directly have been measured when quarks never directly observed in isolation? (Due to a phenomenon known as color confinement.)
6
votes
3answers
355 views

How can I determine the coefficient $k$ in $ \dfrac{dT}{dt} = -k(T - 100 \mathrm{^\circ C}) $?

I recently spend some time on cooking and I'm curious about the time evolution of the temperature of the water. I did some experiment and the temperature is of the form $$ T = 100 \mathrm{^\circ C} + (...
1
vote
1answer
211 views

Universal Sequence and relationship of mathematics and reality [closed]

In "The Special and General Theory of Relativity" Einstein says: How can it be that mathematics, being after all a product of human thought which is independent of experience, is so admirably ...
1
vote
1answer
104 views

Why pulse waves results in wave packets?

I was doing experiments of measuring sonic velocity and I generate pulse waves from sensor 1, but when they are received by sensor 2, I saw wave packets on the oscilloscope, can you explain why? I was ...
10
votes
3answers
939 views

How hot is the water in the pot?

Question: How hot is the water in the pot? More precisely speaking, how can I get a temperature of the water as a function of time a priori? Background & My attempt: Recently I started spend ...
23
votes
3answers
27k views

Is there a compound denser than the densest element?

I'm musing about how to give students an intuitive feeling about density by letting them lift a same sized volume of different materials, e.g. 1 liter of water, a 10x10x10 cm cube of iron, lead etc. ...
1
vote
1answer
274 views

Exploiting the Heisenberg Uncertainty Principle as a means to communicate

It seems as though I've come across a rather unusual conclusion that could either simply be a misinterpretation or a contradictory discovery. I seem to have found a way to utilize the Heisenberg ...
1
vote
1answer
261 views

william herschel discovering infrared problem

when william herschel conducted the experiment of separating white light with a prism and measuring the different colors, he put a thermometer past the red color as a control finding it to pick up the ...
6
votes
1answer
388 views

Is there any experimental evidence to support the Terrell rotation?

The Shapiro delay was predicted in 1964 and observed by 1966, and is now a tool used to measure the mass of distant binary pulsars. The Terrell-Penrose rotation was published in 1959, but I can find ...
6
votes
2answers
507 views

Why propagation of uncertainty is linear?

I'm in doubt with one thing: let's imagine that we have $n+1$ quantities, $n$ of them being directly measured, and the other one being related to the first $n$ by a function $f : \mathbb{R}^n \to \...
5
votes
1answer
321 views

Mechanical shock resistance as a function of shape

I have a system where I'm dropping glass tubes filled with some sample from a certain height, along a track. I can apply a back-pressure of air to push them down faster, and in general the faster they ...
11
votes
1answer
174 views

Have general relativistic effects of the sun's rotation been measured?

I was wondering if general relativistic effects of the sun's rotation have also been measured, like gravity probes A and B measured GR effects from the earth.
7
votes
2answers
469 views

What's the significance of large-scale anomalies in CMB

What's the significance of large-scale anomalies in CMB that are confirmed by Planck? I've read somewhere that the cold spots can provide support for string theory or it may be due to a parallel ...
1
vote
1answer
3k views

Uncertainty in Acceleration given the uncertainty in position

I had a motion detector record the position of a dynamics cart and automatically plot Position vs Time and Velocity vs Time plots in Logger Pro on the computer. If the instrument uncertainty in ...
1
vote
1answer
190 views

Experimental perspective in understanding the Heisenberg Uncertainty Principle

I need to confirm whether or not I understand Heisenberg Uncertainty Principle. So the crucial thing is that you need an "ensemble" of measurements: $$\delta x \delta p \ge \frac{\hbar}{2}.$$ If I ...
7
votes
2answers
6k views

Multiple measurements of the same quantity - combining uncertainties

I have a number of measurements of the same quantity (in this case, the speed of sound in a material). Each of these measurements has their own uncertainty. $$ v_{1} \pm \Delta v_{1} $$ $$ v_{2} \pm \...
10
votes
1answer
283 views

Are oscillations of electron chirality experimentally observable?

Is there any plausible experiment by which chirality oscillations in electrons could be observed experimentally, such as through some analogy to neutrino oscillation experiments?
0
votes
1answer
113 views

Does the method of an experiment always have to be numbered? [closed]

When writing a method for an experiment, does it always have to be set out in orderly numbered steps? Can it not also be a paragraph of text that outlines the method? A mundane example: Place a ...
3
votes
2answers
334 views

What limits the maximum attainable Fermi Energy for a material experimentally?

Either through doping or gating. What are some good terms to search for if I'm looking for some experimentally obtained values for particular materials? I'm particularly interested in what the limit ...
7
votes
2answers
792 views

Does light really “travel”?

From what I've so far understood about light, a photon is emitted somewhere and after some time it's absorbed somewhere else. Have we had experiments that confirm the path taken or something akin to ...