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1answer
36 views

Can we extract chemical energy remotely?

To state directly. Can we use any electromagnetic method to extract energy from fat? Humanity store useless fat inside their body. And to work out mechanically leads to frustration of tireness and ...
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1answer
31 views

Freezing or melting Brine

In the freezing of brine, is it possible to do it at a rater or in such a way that the water only freezes or the ice is somehow isolated? Or conversely is this possible in the melting of brine-ice?
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0answers
41 views

I have got some weird data after a homemade battery experiment

Okay, so i've been searching for some time, for perpetual motion machines of the second kind. So things got into my mind, such as this homemade solar cell. And i thought in my mind:" It's not the ...
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0answers
24 views

Solving for the Nernst Potential in 3D

Hi guys I'm totally stuck on the following question: We know the ionic flux between two chambers due to uneven concentration can be computed by the Nernst-Planck equation $$j = -D_p \left(\nabla C ...
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0answers
47 views

Fitting two semicircles in a Nyquist plot? [closed]

I have done some impedance spectroscopy fist time recently and got the following [Nyquist plot](http://en.wikipedia.org/
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0answers
34 views

How does a battery work?

How does the positive terminal of the battery attract electrons? Does the electric field emitted by the positive terminal attract the electrons?
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1answer
42 views

What's causing the effect of salt in voltage arcs?

I just came across this video demonstrating that salt increases length of voltage arcs. There is no explanation which leaves me quite confused. Does the salt decompose during the process?
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2answers
103 views

How can a fruit be used as a battery cell?

Fresh fruits can be used as batteries for glowing bulbs, but how this is possible? I mean how can electric charges flow through fruits? Do they contain chemicals like cells?
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2answers
103 views

Why is it that the cathodic battery symbol in an equivalent battery circuit doesn't point in reverse for an open circuit case?

I've been thinking about batteries a whole lot, and I've uncovered why the battery symbol looks like a pair of cap-like things in circuit diagrams: it's modeled as two cap-like things using an ...
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0answers
24 views

How does Passivation in Mercury-arc-valve cause “diode” behavior

Does passivation of lead anodes cause them to become semiconductors? Or even become diodes (eg. a p-n passage)? How does this work on an atomar level? This question has been risen by trying to ...
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0answers
23 views

Why is the Poisson - Boltzmann equation not suitable for high potential?

The Poisson - Boltzmann equation is to find the potential whose charge density obey the Boltzmann distribution. If the potential is not large compare to $k_BT$, the PBE can lead to the Debye–Hückel ...
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0answers
27 views

Could a strong AC electric field adversely affect the capacity of a lithium battery?

I run some battery powered test equipment in close proximity (~10cm) to a conductor carrying 25kV (50Hz AC). I find the battery life is much shorter than expected, having checked the current ...
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1answer
82 views

Question on static electricity & electron transfer

Static electricity is caused by the transfer of electrons between substances right? For example, take a balloon and your hair. Both are stable and electrically neutral. So why would electrons jump ...
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0answers
16 views

Zinc is more electronegative than copper,than also why it happens?

Despite the fact that zinc is more electronegative than copper,why it will lose electrons more readily than copper in the voltaic cell due to sulphate ions.
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1answer
54 views

Physical distribution of salt anions and cations during electrophoresis

If I have a volume of $L$ liters of salt water at a concentration of $\approx N$ mM NaCl and I pour it into an electrophoretic apparatus (like this one: ). Once we turn the apparatus on, and set the ...
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3answers
190 views

Why do batteries work?

Consider diagram A. In diagram A a car is at the top of a cliff. Gravity is pulling it down, but it does't move since its on a flat surface. Even though it would be at a lower potential at point B, ...
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0answers
26 views

How to work out bubble size and rising velocity in turbulent flow?

Is there a way to determine bubble size and rising velocity in turbulent flow? I know stokes law but this is only valid for laminar flow.
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1answer
388 views

How does battery cell size affect voltage drop for a fix current load? [closed]

For a fixed current load, will the voltage drop be larger in a small cell or a big cell battery? Why?
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1answer
2k views

Can a saltwater solution conduct electricity forever? [closed]

We know that very pure water does not conduct electricity, but salt water is a decent conductor. This is commonly explained by saying that "the ions carry the current through the solution", an ...
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1answer
119 views

Does an electric field create a pH gradient?

Since pH is a measure of the effective concentration of $\mathrm{H}^+$ ions a solution, I expect that an electric field applied to a solution will create a pH gradient. The higher concentration of ...
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3answers
10k views

Why does connecting a battery's positive terminal to the negative terminal of another battery not create a short circuit?

This is a question regarding the physics behind the observation. I have guessed the answer to the question, but I may be wrong, so I want to wait for the responses before posting it. Some major ...
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1answer
207 views

Electrode potential of an electrode

Suppose we have a voltic cell. In one half cell, we have a zinc electrode (or any other) and in the other we have a hydrogen electrode (or any other). Now, if I say that the electrode potential of ...
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2answers
95 views

What is “species” in the context of an electrochemical cell?

From the Wikipedia entry on Electrochemical cell (http://en.wikipedia.org/wiki/Electrochemical_cell): An electrochemical cell consists of two half-cells. Each half-cell consists of an electrode, ...
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3answers
3k views

Path of an electron through an electric circuit

When a potential difference is applied across a conductor, and if an electron moves from the negative terminal of the battery and reaches the positive terminal, then I want to know if the electron ...
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2answers
225 views

Starting vehicle on hot days

Why it is easy to start the vehicle on hot day than on cold days? Since on winter days it is diffcult to start than on hot days I thought it is due to the low temperature which in turn affects the ...
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3answers
449 views

What is voltage: strict but intuitive definition from accumulator's perspective

I know, that voltage is analogous to pressure for charge, but analogies lie. I don't see charge pressing anything and I don't understand definition of $U=A/q$ (voltage = work/charge), cause I can't ...
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7answers
2k views

Is there any reproducible tested evidence for Ni-H cold fusion?

The main replications of cold fusion, the ones that are beyond reproach, used Pd/d as the system. But commercial developers have often claim to use Ni-H to achieve similar effects. The claims include ...
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1answer
233 views

Electrical Resistance and chemistry

Can some one describe or explain what happens when too much current is passed through lets say a copper wire, I am looking for an explanation to do with physics and chemistry. For instance we have ...
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2answers
265 views

What's up in this SPAWAR video?

Here is a video presentation of infrared recordings of anomalous heating in a deuterium palladium cell: ( youtube video) (see also this presentation if you want more detail, and have time). There are ...
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1answer
328 views

Can anyone explain this demonstration with a helium balloon?

See the YouTube video (click) named "Testing the Magnetic Nature of MagneGas.mp4". A helium balloon is attracted to a metal bar.
2
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1answer
697 views

Solving Poisson-Boltzmann equation for flat surface without excess salt

I'm trying to understand the solution of Poisson-Boltzmann (PB) equation as I read it in a review. The surface is uniformly charged and flat. I am only considering the $x$ direction. The PB equation ...
4
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1answer
470 views

Addition of a neutral electrolyte to water— how can it increase conductivity?

Sparked off by Is sea water more conductive than pure water because "electrical current is transported by the ions in solution"? This question really belongs on chemistry.SE, which is ...
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1answer
7k views

Is sea water more conductive than pure water because “electrical current is transported by the ions in solution”?

Apparently, electrical charge is transported by the ions dissolved in water, is this true?
1
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2answers
371 views

What happens to body chemistry at the speed of light? [duplicate]

Assume that I'm traveling at the speed of light in one direction. My brain is also traveling at the speed of light in that direction. Presumably there is at least one receptor site in my brain that is ...
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0answers
97 views

Is it possible to transform chemical energy in electrical energy by modifying the equilibrium constant?

Considering a Daniell cell, is it possible to create endlessly electrical energy by using atmospheric temperature (for exemple) variations to modify the reaction's eqilibrium constant ? I apologize if ...
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2answers
211 views

Introducing emf of a chemical cell as a hint towards quantum mechanics

Today I had a discussion with a colleague who teaches electricity and magnetism to 2nd year undergraduate physics students. He is seeking the best way to explain how is the emf generated inside a ...
6
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1answer
574 views

What is highest water pressure at which electrolysis can be performed?

What is highest water pressure at which electrolysis can be performed to derive hydrogen and oxygen? Does the dielectric constant of water, which which lowers as pressure increases, have an effect on ...