Cell Definition and 899 Threads

Why doesn't charge move back to the low potential inside of the battery,why does it go through the circuit?

is it really ok to assume that internal resistance of a cell is absent in a circuit ?

Homework Statement uData is a 30x5 matrix with numbers. name_Database is a 30x1 cell array with strings of Names (e.g. Fake Subject 1, Fake Subject 2, Bob). What would fix the code so that the data aligns? (please see image for the misalignment). Homework EquationsThe Attempt at a Solution...

A number of my relatives believe that radiation from cell phones is dangerous. After doing a bit of reading, I've found that the general scientific consensus is that this is not the case, and I myself don't see how low power, low frequency, non-ionising radiation can cause e.g. brain tumours -...

Consider two adjacent people speaking in cell phones. Why the signals don't interfere with one another? Does each phone communicate with a distinct frequency? If so, how?

So I have an old flip phone here that I wanted to turn into a portable battery pack because its winter break and I am bored. Whole thing is apart and good to go but I was wondering if there is any way to reverse the current. Obviously charging it one way, and then when you use it as a battery...

Hi All, Having plotted a cell growth curve (fluorescence vs days), I have found that during the lag phase, the fluorescence values decrease. I haven't come across this previously during lectures and can't seem to find any examples online to help explain it. My only thought was that cell death...

http://www.sciencedaily.com/releases/2014/11/141125111816.htm?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+sciencedaily%2Fmatter_energy%2Fsolar_energy+%28Solar+Energy+News+--+ScienceDaily%29 Pretty cool use of a mass produced product but how much do you think a Chuck Norris disk...

As I know, when a string of solar cells connected in series, if one of the cell is shaded, it will be reverse bias due to current mismatch and the voltage can be very high, say, 20V. But in short circuit condition, the overall voltage should be zero, if other cells are in forward bias, how can...

The current and the voltgate from solar cell are verry small, so can i add a amplicifer circuit? And How add?

Can a small fusion cell be created? If no, is it due to low confinement time it would have or something else? Thank you.

If electrons always flows from an area of high density to low density, why is it necessary for the ions in a cell to flow across the electrolyte as well. It seems that charge should be able to flow from the anode to the cathode without the need of these ions flowing as well. Why are these two...

Homework Statement a) http://i.imgur.com/LrWxrEX.jpg b) http://i.imgur.com/3YmN3Rv.jpg Homework Equations A halt-wave rectifier(a) is used to charge a battery E.The battery is rated at 12V 100Wh. Average charging current for the battery should be 5A.The primary input voltage is 120v at 60Hz...

Homework Statement The fraction of volume unoccupied in the unit cell of the body centered cubics lattice is? Homework EquationsThe Attempt at a Solution I got the volume occupied by the atoms as (8/3)πr3. I am not sure if it is right. I just assumed that all the atoms were of same element. I...

Homework Statement CsCl has a BCC unit cell containing 2 atoms, Cs in the origin of the cell and Cl at the centre of the cell. Describe the CsCl unit cell in terms of its primitive cell+basis. Homework Equations R = n1a1 + n2a2 + n3a3 ~ R is the vector which relates one point of the lattice...

Hi, I haven't posted anything on here in a long time, but thought somebody here could help me out. I am building a fuel system for an endurance sports car. I have a sealed 0.6 gallon collector in the fuel cell with three 75gph pumps, capable of 95psi feeding it, through 3/8" hose. It then...

I have a monoclinic conventional cell with atomic positions obtained from a structural database, and I need to know the primitive cell for that lattice. is there any code to do that like vesta or crysden thank you in advance

If you wanted to separate the P and N type semi-conductive layers and place a diode (which contains a P-N junction) between them so that current would still travel in the correct direction, could you? I want to separate them so that I can insulate the N-type layer with a reflective metal. I just...

Hello, I'm trying to design a strain gauge load cell for force measurments. I have few questions regarding that. Q1: how to calculate the minimum froce that my load cell can detect? Q2: how to calculate the FSO(full scale output) of my load cell? Q3: Is there any way to measure the...

I'm wondering about the importance of the electrolytic solution in an electrochemical cell. For example, we have Zn/ZnSO4 and Cu/CuSO4. According to the electrochemical series, Zn will reduce Cu, and we will have a reaction. Zn(s) -> Zn2+(aq), Cu2+(aq) -> Cu(s). So there MUST be Cu2+ in the...

Basically, I've written some code that take as inputs 1)Basis vectors 2)lattice translation vectors and computes the structure factor of the basis, producing a diffraction pattern. I'd like to begin incorporating subtle differences between atoms, so I want to compute the structure factor of...

Hey folks, Sorry if this is a boring topic or if it's posted in not the best subject but here goes. I'm working on a solar-power related project and will have a display set up indoors. The cells are rated at up to 10V and 150mA. Under ambient artificial light we can get the voltage...

"Volume of a primitive cell is independent of the choice of the cell." Why?

Hi, I am wondering as to how to define the boundary condition for a shape in a unit cell. Just imagine that the shape is the hole for the unit cell. Hence, for a constant thickness on the untextured boundary, thickness is, let's say C, then for the circle, it's C+depth. For example for...

After specifying the primitive vectors of a structure namely (a,b,c) in Wien2k, one has to specify locations of atoms in unit cell.There are three components X,Y,Z which determine the atom location. I want to know whether "X,Y,Z components" are corresponding to vectors a,b,c or they are...

Hi, I was trying to design Molten NaCl battery (cell ) , but found most of information about Li based salts. Ihave a muffle furnace that can melt NaCl , need to know what anode , cathode materials , what supporting accessories or assembles to design one. can some one help ?

Hello, 1) I am looking for numerical data behind plots like this one. 2) Also, any information on the experiments the data comes from would be helpful. Are cone cells directly measured, or does it involve a human matching colors to a pure color light source? 3) Will I be able to write a...

I am not a (real) engineer, but have undertaken an ambitious project which contains some technical intricacies I have to learn on the fly. My first question (of many to come no doubt) is about strain gauge load cell technology - specifically powering the device. My project requires a battery...

Homework Statement The redox reaction of peroxydisulfate with iodide has been used for many years as part of the iodine clock reaction which introduces students to kinetics. If E°cell = 1.587 V and E° of the cathode half-cell is 0.536 V, what is E° of the anode half-cell? S2O82–(aq) + 2H+ +...

I'm trying to find out what material might best block or limit radio frequency interference (or at least I think that's the problem, as I understand it). I have a phone, the antenna inside the phone is next to a chip that controls a touch button. Whenever the phone boosts the signal to...

Hi, I'm currently working on a project: I'm trying to make a cell phone charger from an Altoids tin and batteries. I know there are countless tutorials out there, but I want to understand why everything happens and how it works. I'm getting to each problem individually, so that I can find a...

Homework Statement Write a line of MATLAB code that uses the cell array A to generate the string 'Cal Golden Bears'Homework Equations The Attempt at a Solution A = {'Cal', 'Golden', 'Bears', [5 7], {[1 2 3 4]}} A = 'Cal' 'Golden' 'Bears' [1x2 double] {1x1 cell} The...

Hello I am trying to fabricate a Si reflecting solar cell. When a Solar cell is exposed to radiation and connected to external circuit, the current will start to flow through the circuit. So I want to know how does the Reflectivity of silicon change with the current( or conductance).[...

Homework Statement A hip kid is sitting down listening to music on his cell phone. The ear buds connected to the phone are inserted in his ears firmly and the phone is in his pocket. As the kid pulls something out of his pocket, the phone falls out and freely falls until just centimeters above...

I am very interested in biochemistry, and in particular the metabolism of the cell. Important molecules for cell metabolism are ATP (and ADP) and NAD+ (and NADH). ATP, ADP and NAD+ are ions: ATP and ADP have negative charge (as have the free phosphate ions) and NAD+ has positive charge. But the...

Hi everyone, I am working with a solar cell realized with a metal-semiconductor junction. I need to find an expression for the short circuit current of this solar cell, but in the literature I have only found models for the standard case of a pn junction solar cell. Does anyone know a...

What is the difference between an android cell phone and a non-android cell phone?

Which are all the possible combinations of chemical elements that a common people can use for manufacture an electrical cell that no needs of special care? (say me from better to worse, please) Also, the combination Zn/Cu is the standard combination or is just a combination among several...

In the following http://electrons.wikidot.com/solar-cells it mentioned that how and when n-side becomes positive?

why do we make composites with graphene oxide not with graphene ? if there is a problem to do composite with graphene ?

Homework Statement A cylindrical conductor of length l and inner radius R1 and outer radius R2 has specific resistance ρ A cell of emf e is connected across the two lateral faces of the conductor. Find the current drawn from the cell. The Attempt at a Solution Consider a thin shell of...

Hello Forum :), Please find attached my problem. The solutions is also there. BUT, I do not understand why my teacher does not simply assume pH=0. It seems as though we are using the standard hydrogen electrode (ie 1M H+ in solution!).

have two solar cells which I have connected in Parallel to increase the current provided to the system. I want to calculate the maximum Power point tracking for my solar cells. There was no information provided by the seller except the one below. I have attached the open circuit reading of...

1. estimate the fermi energy for lithium... the crystal structure of lithium is a bcc with a unit cell size of 3.5*10^-10 m [b]i need n, which equals N / V. if i divide by per atom, then i get (N/atom) / (V/atom) = valance / (V/atom). my question is how to get the volume per atom...

Trying to work out how to do this. I know the answer is B but don't know how. Internal resistance is negligible so I assume I just use I =V/R. I've tried using sample values for R eg 5 and V =10V giving I as 1.3 but am no closer to 2/3. What am I missing?

Not sure if this is the right section for this, I apologize in advance. I have a project to do and my goal is to measure the efficiency of a solar cell INDIRECTLY. I am not sure how to do that. The equation for the efficiency of a solar cell is η = P/E*A. Where P is the cells...

Hey guys! I'm not sure if I solved this correctly. If you could please take a look at my answers I'd really appreciate it. Thank you in advance! (I tried using the super subscript option but I started to confuse myself because of all the coding so I just stuck with the up arrow (^) I hope you...

Model NO: LG-VX11000 Battery model: LGLP-AHLM Battery states Lithium-Ion Polymer Battery 3.7V 950mA I do not have my charger.

I've read about why it would be nearly impossible for an individual to construct a working home built nuclear reactor (of any variety), but I've never understood why a home built nuclear battery couldn't be constructed (think Henry Moseley's work). The size and power output would be impractical...

Hi. I am currently in a situation where I have a function handle giving as putput an array of doubles. I would like to convert this to a cell array of function handles, each giving a component of the previous array. The original function handle is produced by a built-in MATLAB function, so...