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

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1
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0answers
32 views

charged oil drop in electric field [closed]

I am currently doing coursework for my A2 physics course. I am dropping a charged oil drop in a horizontal electric field and I was wondering how to calculate how much the droplet would deviate given ...
4
votes
3answers
278 views

Thought experiment using quantum entanglement in position and its effects

Consider we have two atoms $a$ and $b$. They are entangled with each other in position and momentum, with some wavefuction describing them in position space that is $\Psi(x_a, x_b)$. This ...
2
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0answers
24 views

Experiments proving/disproving extra dimensions [duplicate]

I have been recently reading quite a little about Kaluza Klein theories. I am still far from mastering this but I am curious if any experiment that may disprove or give hints of the existence of extra ...
13
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5answers
1k views

Why is it easier to break a tightened or stretched string than a loose one?

I want to know, why is it that it is easier to cut through a string which is tightened then a loose one? The question arose when I was watching - "What Happened Next?". In a part, they showed two ...
2
votes
1answer
125 views

Specific heat of aluminium as a function of temperature

I am trying to find the curve describing the specific heat of aluminum as a function of temperature between about 50K to 300K(or room temperature) for an experiment I am doing. Ultimately I need to ...
8
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2answers
2k views

Which is the smallest known particle that scientists have actually *seen with their eyes*? [closed]

Which is the smallest particle that has been actually seen by the scientists? When I say "actually seen", (may be using some ultra advanced microscope or any other man made eye, using any wavelength ...
7
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3answers
98 views

Experimentally Verifying a Clock's Accuracy

So recently one of my professors went off on a tangent, and we ended up discussing atomic clocks and how they work, which is something I've always been fascinated with and thoroughly enjoyed. But it ...
1
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1answer
74 views

Measuring a fluctuating quantity: Instrument error vs. uncertainty, or both?

Say I am measuring a quantity $x$ in physical system whose true value is approximately sinusoidal in time. I have an instrument to sample this quantity, for which the manufacturer gives an accuracy ...
-4
votes
1answer
162 views

Is the interpretation of BICEP2 data being due to “graviational waves” concerning considering the negative results of the LIGO's experiments? [closed]

Gravitational waves are a yet unproven idea... The lack of positive results from LIGO indicates these are still theoretical constructs not yet supported by experimental data. Is not the explanation of ...
0
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3answers
89 views

Single mode fibers

Is it possible to focus white light into a single mode optical fiber? I thought no because in order to focus it should be a solution to the Helmholtz equation but I am not too sure about it. Also ...
-1
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1answer
122 views

What are the problems in analyzing an experiment with non-ideal collisions? [closed]

For a two-dimensional collision experiment, I must explain in one of the questions the problems in analyzing a non-ideal two-dimensional collision. As the question states: Suppose that the ...
1
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1answer
92 views

Numerical aperture of a lens

Using a laser setup, I was asked to determine the aperture of a given lens and then use some geometrical arguments and compare the theoretical value from the manufacturer and the experimental value. ...
5
votes
2answers
364 views

What experiments compete with BICEP 2, and when are their results expected?

The recent results of the BICEP 2 experiment published on March 17th 2014, has generated a lot of media attention, with the general consensus being that "this is a major discovery" perhaps leading to ...
0
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3answers
72 views

Creating electricity from mains water pressure.

Could someone cleverer than me help me out? I had a crazy thought going through my head the other day and I can't lay my mind to rest until I get an answer. Q. How much energy could be produced by ...
71
votes
5answers
5k views

What was the major discovery on gravitational waves made March 17th, 2014, in the BICEP2 experiment?

The Harvard-Smithsonian Centre for Astrophysics held a press conference today to announce a major discovery relating to gravitational waves. What was their announcement, and what are the implications? ...
0
votes
2answers
100 views

Photoelectric effect: current vs wavelength

In an experiment where the type of metal,intensity of light and potential difference across a battery is kept constant at 2V the results show that an increase in wavelength, obviously in turn ...
1
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5answers
101 views

EPR paradox: instantaneous vs very fast?

An EPR quantum experiment can be explained by instantaneous collapse of the wave function regardless of the distance separating a pair of entangled particles. But do we have the certainty that the ...
2
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0answers
40 views

need data-point: count rate of APD (avalanche photo-diode) for specific aperture and stellar magnitude

I hope lab / experimental physics is fair game for this web-site. If not, sorry! I'm designing a sensor system to perform specialized [astronomy and space-sciences] experiments, and need a "reality ...
1
vote
1answer
38 views

Measurements for thermal diffusivity of graphene?

We have known for a long time that graphene has in-plane thermal conductivity ranging between 2000 and 4000 $W m^{-1} K^{-1}$. But in order to model heat transport on a sheet of graphene, we need more ...
4
votes
1answer
168 views

Why would a pendulum experiment give $g > 9.8\ \mathrm{m/s^2}$?

I am taking an introductory lab course in which we've done an experiment on the physical pendulum. We've seen that for small oscillations, the period is ...
1
vote
2answers
55 views

How organic impurities in the air affects laser?

We have a Nd YAG laser pumped Optical Parameter Oscillator in our lab. A technician came to our lab (my professor called him for its maintenance) and while he was working on it, he told me that ...
1
vote
1answer
59 views

Getting nonphysical results when solving for the index of refraction of a slab?

I'm trying to computationally find the refractive indices (real and imaginary) for a thin slab suspended in air (so the only indices to deal with are air and my material's). I've experimentally taken ...
3
votes
1answer
141 views

Electrons skip randomly around their orbits

I read where the electron (as well as a few other particles) skips around in its orbit randomly rather than move around the orbit smoothly. This effect has been repeatedly observed in the laboratory ...
3
votes
0answers
25 views

Experimental results regarding non-extensivity in small systems

From a statistical mechanics point of view, the extensivity of thermodynamics arises from the fact that we can neglect interaction terms in the Hamiltonian. This allows us to infer that when we put ...
0
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0answers
34 views

Quantum distance ladder

There is a lecture on how facts about the cosmos can be derived form rather simple observation. Is there an analogy for the small scale? Is there a technically simple observation that would imply, ...
1
vote
3answers
76 views

Cart on Ramp with Varying Acceleration

For a lab that I have to do, the teacher has given me a data table of the displacement of a cart on a ramp after successive intervals of time. I have used this data to derive the velocities and ...
2
votes
0answers
43 views

Fractional quantum number induced in a soliton profile

It has been known there is fractional quantum number induced in a soliton profile, such as this Jeffrey Goldstone and Frank Wilczek paper and many works of Jackiw. For example the electric charge ...
4
votes
1answer
237 views

Calculating Lyapunov exponents from a multi-dimensional experimental time series

Wolf's paper Determining Lyapunov Exponents from a Time Series states that: Experimental data typically consist of discrete measurements of a single observable. The well-known technique of phase ...
0
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0answers
44 views

Brewster angle and perpendicular component

Fresnel's equations give that at Brewster's angle, the parallel component of the incident light is zero. The reflected perpendicular component is not zero, though. We can "remove" this component using ...
1
vote
1answer
37 views

2nd - 3rd Year Physics Labs [closed]

I'm looking to propose a new physics laboratory experiment, does anyone have any particularly fond memories of an experiment they carried out whilst at University? I'd like to include a section that ...
2
votes
0answers
228 views

How would you go about finding the natural frequencies (resonance frequency) [closed]

How would you go about finding the natural frequencies of solid materials like wood (e.g., teak, pine), stone (e.g., marble, granite) liquid, etc?
1
vote
2answers
62 views

Reference frequency

In my experiment, I have to obtain a relation between magnetic field of a solenoid and the applied Vp-p. The setup is as follows. http://www.teachspin.com/instruments/faraday/ Does my choice of ...
-2
votes
2answers
37 views

In how big percentage of gravity core does play role in?

If something would take whole core of earth and done this $(((coreearth)-(restofearth)):coreearth)*100=X$ What would X be? In short, which part of our planet ...
2
votes
5answers
81 views

Addition according to significant digits

I have been studying about significant digits and addition rules and I can't quite digest the rules of addition completely. It states that in the answer number of decimal places will be equal to the ...
2
votes
2answers
108 views

Experiment under ambient light

I performed the following experiment for Faraday rotation, Verdet constant etc. http://www.teachspin.com/instruments/faraday/ However, I have a concern. Does the external light actually affect ...
3
votes
1answer
52 views

Neutrino Nuclei Coherent scattering and the Dark Matter lower wall

Suppose that current and new forthcoming dark matter direct detection experiments find no evidence of Dark matter events and exclude interactions of hypothetical DM particles (like LSP or similar) in ...
1
vote
0answers
15 views

Change in Angular momentum of a spinning superball

I throw a superball towards the ground and when I do I intentional induce a spin on the ball so that the ball is spinning towards me on the descent. As soon as the ball hits the ground and comes back ...
0
votes
1answer
30 views

Plasma Treatment of LaAlO3: Surface Roughening

I'm trying to understand something I've observed in exposing LaAlO3 substrates to an oxygen plasma (yielding atomic oxygen). In literature, these substrates are frequently "cleaned" in a oxygen rich ...
1
vote
0answers
61 views

Different phase in capacitively coupled RLC circuits

I was trying to work with some data for a lab report I'm writing about capacitively coupled RLC circuits. The setup is pretty simple and looks like that: Where $C^{'}$ is the coupling capacitance. ...
0
votes
0answers
51 views

Measurement of speed of static electric field propagation?

Could one measure the time delay between charging up an electrode and measuring the static electric field at some distance? For example I've looked up the specifications of an Electric Field Meter ...
4
votes
1answer
121 views

Couder-Fort Oil Bath Experiments and Quantum Entanglement Phenomena

The oil bath experiments of Couder and Fort have been able to reproduce various "pilot wave like" quantum behavior on a macroscopic scale. Particularly striking is the fact that the double-slit ...
1
vote
1answer
71 views

Waveguides Transmission Mode Determination

How do I know if I have TE, TM, or TEM rectangular conductive waveguide? For instance, I am doing a lab where we want maximum magnetic field in the waveguide, does that mean we want the TE because ...
4
votes
1answer
278 views

Is cooling really exponential?

I did the following experiment: I took boiling water, put a thermomenter (from Vernier hooked up to a TInspire calculator) into it and pulled it out. Then we started measuring the temperature it read ...
3
votes
2answers
525 views

Why doesn't the water spill out?

In this experiment, a number of coins are put into a cup full of water, without spilling it. http://www.youtube.com/watch?v=N2mKpZHnEzw Firstly, let me clarify one thing. If you fill up a cup ...
0
votes
1answer
59 views

Dead time in data acquisition

I am creating a data acquisition software, based on Sparrow's Kmax. There I would like to add a feature that will show the system's dead time. I have already a text field that shows the real time and ...
0
votes
0answers
17 views

Can unexposed PMMA be reused (successfully exposed) after development?

Can unexposed PMMA be reused (successfully exposed) after development? To clarify, PMMA is exposed using an electron beam in an SEM, and then the exposed areas are removed using a developer solution, ...
1
vote
2answers
59 views

objects distorted by the earths curvature

We are doing a project where we hope to make people think about the fact that the earth is round. We want to imagine if we in London could see others places in the world and how the earths curvature ...
3
votes
1answer
157 views

How to compensate ray displacement caused by refraction in glass slab

I need a nudge in the right direction, i guess (this is not a homework question). I want to calculate the total length of a ray from an emitter to a target which passes through a slab with known ...
8
votes
2answers
520 views

Does a muon detector on Earth's surface correctly measure the mean lifetime of a muon?

Just a simple question. Does a muon detector on Earth's surface correctly measure the mean lifetime of a muon? I would think the answer is no because most muons detected are created about 15 km above ...
2
votes
0answers
38 views

Can a value of “length, in meters” be attributed to a pair of ends which are rigid (but not at rest) to each other? [duplicate]

The definition of the SI base unit "metre" [1] doesn't seem to rule out explicitly that a certain value of "length, in meters" could be attributed to a pair of ends which are rigid to each other, but ...