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Image of an electron

An "image" is formed from lots of light rays leaving the same object. For instance, when your eye forms an image of a symbol on your computer screen, like this symbol, $$ \sum $$ what's ...
rob's user avatar
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Image of an electron

You can't see an electron with a microscope.
trula's user avatar
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An instrument for sensitive time interval measurements?

Are there any instruments that utilize the speed of light or sound to measure the fall of an object? You could arrange for the object to trigger an electrical switch as it falls, and when it lands, ...
The Photon's user avatar
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1 vote

Experimental status/test possibilities for baryon number conservation in LHC?

LHC events are too messy with too many missed or misidentified particles for direct baryon and anti-baryon counting to be an effective method to look for Baryon Number Violation (BNV), but limits can ...
David Bailey's user avatar
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To understand relativity in time with time dilation experiment

The point people often struggle to appreciate in SR is that time dilation is symmetric between two inertial reference frames. What that means is that if you are time dilated in my frame, then I am ...
Marco Ocram's user avatar
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1 vote

Experimental status/test possibilities for baryon number conservation in LHC?

The most important thing to keep in mind is that the LHC cannot directly check baryon conservation because of limited kinematic coverage of the detectors (many fragments fly down the beam pipe), and ...
Thomas's user avatar
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2 votes

How is my hot plate inside an aluminum-lined styrofoam box not violating the laws of physics?

I've increased the rate of energy input into the system by 13.997W, but now it's radiating 21.89W more energy as a result! That would be surprising if all of the energy were leaving the system. But ...
BowlOfRed's user avatar
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To understand relativity in time with time dilation experiment

You are right it is symmetric, So in the moving train you age the same as in the nit moving. It is just the other observer who thinks there is a difference. So if there were twins, they just age the ...
trula's user avatar
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2 votes

Experimental status/test possibilities for baryon number conservation in LHC?

The paper whose press release you cite looks at a number of baryons and other hadrons: In this Letter, we report the most precise estimation to date of $μ_B$ and $μ_Q$ obtained from a set of ...
rob's user avatar
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3 votes
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How do materials scientists find and make candidate materials?

A common method throughout physics for finding new things is to take something known and vary one aspect of it. With chemical compounds, there are many options. For experimentalists who do materials ...
just a phase's user avatar
1 vote

Which one to choose as the uncertainty?

The standard deviation of your measurements will be the same as long as your measurement technique does not change. But the standard error on the mean, $\sigma/\sqrt N$, reflects the fact that ...
rob's user avatar
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1 vote

Which one to choose as the uncertainty?

The uncertainty should be reported as the standard deviation of the measured values. The uncertainty is reflected in the spread of values obtained in the measurement process. You would want to use the ...
Albertus Magnus's user avatar
1 vote

What is the average time taken to carry out an average experiment in the lab?

This is like asking "how long is a piece of string" ? Some experiments require the design and construction of specialist equipment, which can take many months. Some are simple to set up but ...
gandalf61's user avatar
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3 votes
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What is the upper limit of size for diffracting an object?

As far as I know the largest object that has been successfully diffracted is a oligoporphyrin molecule with a molecular weight of about $25000$. This was done on 2019 and is reported in Quantum ...
John Rennie's user avatar
1 vote

What is the upper limit of size for diffracting an object?

Electrons are a relatively light particle, and therefore have a relatively long De Broglie wavelength. Electrons have been diffracted through the spaces between atoms in a crystal. A proton is about $...
mmesser314's user avatar
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1 vote

How are states of matter determined experimentally?

There are a few things people typically measure in experiments to diagnose a phase of matter (or critical point / line separating two phases). Conventional phases of matter are diagnosed by the ...
just a phase's user avatar
2 votes
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Why fiber optic Sagnac interferometers don't produce multiple interference fringes

The fibre is a single mode fibre and the phase is therefore associated with the mode as a whole varying along the longitudinal direction. The interference thus only determines which output port gets ...
flippiefanus's user avatar
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0 votes

Why does a photomultiplier tube (PMT) traditionally present better signal-to-noise ratio (SNR) than an avalanche photodiode (APD)?

I don't know much about the difference between PMT and APD, but if PMT has a higher gain than APD, than perhaps a larger portion of photons reaching the PMT can be detected than APD. The number of ...
FoxFox's user avatar
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1 vote

Ball trajectory in the game of pétanque - unexpected drag results

You should be able to easily determine the drag experimentally by performing a simple vertical drop of the ball from a known height and timing the drop. Greater drop height gives better accuracy and ...
Stevan V. Saban's user avatar
0 votes

How should I clean a part before installing it in a vacuum system?

Please refer to the summary 'Cleaning and surface properties' published by CERN's Technology department, which is commonly used for UHV components in particle accelerators. You can equally consult the ...
Michal Haubner's user avatar
5 votes
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Breaking the rock using eggs

Easy, if you allow for relativistic speed. At a few tens of kilometers per second (about earth's orbital speed), minor forces like chemical bonds or electrostatic attraction between electrons and ...
cmaster - reinstate monica's user avatar
12 votes

Breaking the rock using eggs

If water can create the Grand Canyon and the Dakota Badlands, then with enough eggs and time you can certainly break a rock. Just throw eggs at the rock continuously for a million years or so.
gandalf61's user avatar
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