Ev Definition and 65 Threads

  1. mfb

    A Thorium-229's excited state at 8.355733554021(8) eV

    Missed this on arXiv, now it's published: Frequency ratio of the 229mTh nuclear isomeric transition and the 87Sr atomic clock They measure the frequency of the transition radiation with an uncertainty of just 2 kHz or 1 part in a trillion. That's not beating the best atomic clocks yet, but it...
  2. Addez123

    Confused about quantum tunneling through 200V not eV

    I have the equations to calculate transmission probability, my problem is that the barrier is given in Volts not electron volts. $$200V = e \cdot 200 eV = 3.2 \cdot 10^{-17} eV$$ I am not even sure if that's a correct conversion. But if it is then this "barrier" is extremly small and 99.999%...
  3. dlgoff

    Panasonic has announced it will begin building its EV battery

    I moved to Kansas from Arkansas when my father got a job at the Sunflower Army Ammunition Plant in Desoto Kansas. Now that plant will be making Batteries for electric autos. I wish my dad was still alive to see this.
  4. J

    Finding the Best Batteries for a 48V EV Motor

    How did you find PF?: Google Search Hi have a 48 Volt EV motor of which I will be modifying for belter performance I am unsure of the specs i have contacted the supplier and awaiting a call back I have Toyota coaster And I am allowing up to 5000 KG in Weight How many batteries do I need and...
  5. J

    Why isn't the scaling factor included when stating particle mass in eV?

    not technically a homework question, just figured it fit here.
  6. mfb

    I New cosmological neutrino mass constraint: sum<0.09 eV at 95% CL

    arXiv: On the most constraining cosmological neutrino mass bounds From neutrino mixing we know that an inverted order (two "heavy" neutrinos, one light neutrino) needs a sum of masses of at least ~0.09 eV, while the normal order (two light, one "heavy") can have a sum as low as ~0.05 eV. The...
  7. E

    What tests should I do for lightening an ev chassis

    Hi, I am an engineering student and for my project I have decided to try and improve the range of ev through chassis lightening, the main point I'm focusing on is using a carbon fibre material, so I was just wondering if anyone could tell me what kind of tests I would need to do on Ansys or...
  8. Gh0stS3C

    Doubt regarding conversion of eV to V

    So I know exactly how to solve this question with the relevant equations. However problem I ran into was how I substitute for K.E (Kinetic Energy). I asked one of my teachers for help. She said that since the voltage applied stops the experiment, it is equivalent to the energy of the electron...
  9. DariusP

    I EV per Torr*cm -- What does it mean?

    I was reading about this https://en.wikipedia.org/wiki/Nitrogen_laser and it says "80 to 100 eV per Torr*cm pressure of nitrogen gas". I'm finding this a little bit confusing. It needs some specific amount of energy in a centimeter of volume with 1 Torr of pressure?
  10. B

    Automotive EV hub motor torque for pulling a roller

    I am working on a 500 kg roller, which I want to pull using electric motor. I am considering hub motor, since it is easier to frame a basic ev with it. Now I need to know the capacity of the hub motor, I need to choose. Roller weight = 500 kg Frame weight + driver weight = 150 kg speed required...
  11. Z

    Calculating gear ratio from the motor's graph for an EV?

    Dear community, For my electric vehicle project I want to select a gear ratio (single) of my gear box and send this information to the supplier. In order to calculate this ratio I thought of the following steps but am not sure and want some expert to recheck and answer my queries: 1. Calculate...
  12. ckcurtis

    500cc 50hp electric motor swap

    Hi, I own a 1993 ex500 with that is having engine problems, I would like to swap the motor for one that is has more or equal power. The best specs I can come up with are these the motor puts on the rear wheel, HP 50, Torque 31 ft-lbs, top speed 130mph, I am looking into getting a DC-liquid...
  13. L

    Compare and contrast a 2.2 eV photon with a 2.2 eV electron

    Homework Statement Hey everyone, So my teacher assigned a mini project just before our finals and I was wondering if someone could look over my work and my calculations. I just want to make sure I understood everything since my final exams are coming. Here's the assignment. Compare and...
  14. Raazi

    Automotive Electronic Torque Managment in an EV

    Hi, I am a beginner in terms of mechanics and am an electrical engineer so I apologize in advance for asking what may be trivial questions. I am attempting to create a prototype design for an electric vehicle (truck) in which I am mimicking the Telsa drive train configuration but I am stumped...
  15. T

    What is the efficiency and power loss of electric vehicle motors?

    I'm looking for a good figure out there like this to describe electrical vehicles. I know EV's are on average 60% efficient but I'm looking to discuss the losses and percentage loss at the systems in an EV. Anyone have any insight?
  16. KaleLetendre

    Automotive Building an Efficient Electric Vehicle from Scratch

    Lets say we have a car with no engine, just a shell. We want to create an extremely efficient electric vehicle. If we have unlimited resources and man power how would you go about making this vehicle?
  17. N

    Are the energy levels in EV known for glass material

    So in glass, transparent liquids, and plastics is the eV for the electron known to science. The eV levels for electrons in gases are known like in hydrogen, and helium, but are they known for glass, and transparent liquids, and plastics. Or is it just too discernable to get. I am grateful for...
  18. N

    What is the magic number in eV for electrons in glass, transparent....

    - liquids, and plastics for light to transmission completely through the material. Is this eV level known in glass, liquid, and transparent plastics, for electrons to transmission light. Physicists say that "In most solid or liquid substances, the electron structure is so complex that...
  19. N

    Can microwaves either change the eV of electrons, or move....

    -the electrons to the same shell levels of glass as the microwaves pass through and heat the material, or move electrons in a opaque material to the same energy levels, or shell levels of glass, and transparent liquids, and some plastics. In a microwave the waves traverse food, and heat the food...
  20. T

    Charging EV with varying input power

    I wanted to post this as a thought experiment. I wanted to preface this by saying I do not plan to build/experiment with anything being discussed as high currents/ high voltages are being dealt with and I am no expert.I am curious on designs for a system that will take the energy from a...
  21. Alanay

    I I finding the EV of the possible outcomes

    I'm making a Bitcoin gambling game with some developers. But I need help from you crazy good mathematicians out there! I need to know the "kelly criteron" or "EV" of the possible outcomes in the game. How the game works: The game is basically a grid of 1-100 numbers. Every 10 seconds a number...
  22. L

    How to change density of states to eV

    I know that if I multiply e^3/2 (e= 1.602x10^-19) to the unit below I can change it to eV Can somebody help me I don't know why
  23. S

    What Is the Minimum Energy Required to Break a Molecule Apart?

    Homework Statement Potential energy in a molecule[/B] (b) The figure below shows all of the quantized energies (bound states) for one of these molecules. The energy for each state is given on the graph, in electron-volts (1 eV = 1.6 ✕ 10-19 J). What is the minimum amount of energy required to...
  24. N

    Does anybody know the energy shells eV for glass, and solid carbon?

    Carbon. So is it known what energy levels for electrons in glass atoms are in eV to move to a higher shell level. Glass does not absorb any light, except UV. but what is the eV for the glass electron to get excited and leave the ground state, and move up to shell level 2, or energy band 2. Also...
  25. Questions554

    Why is the conversion from eV to Kelvin so high?

    I mean eV are something like 1.6x 10^-19 joules but somehow 7eV corresponds to 81121 K?? At that temperature you should have a lot more energy than 7eV! No?
  26. Avatrin

    Mass in eV over speed of light

    Hi! I know the mass of, for instance, an electron can be express in units of electronvolts over speed of light squared. However, I am not sure how to use it. When I have to calculate \frac{\sqrt{2mE}}{\hbar}, do I have to multiply m with the speed of light squared to get it in meters per second...
  27. grandpa2390

    Converting eV to Joules vs eV to V

    Homework Statement Is this true? Homework Equations 1 eV = 1.6e-19 J 1 V = 1.6e-19 eV The Attempt at a Solution I did a bit of googling and it just seems strange. eV multiplied by elementary charge = Joules ev divided by elementary charge = Volts
  28. E

    Calculating Properties of a 2.2 eV Electron

    Homework Statement I need to figure out the energy, rest mass, speed, wavelength and momentum of a 2.2 eV electron. Thats all it says. Homework Equations Ek = 1/2mv^2The Attempt at a Solution I don't understand what 2.2 eV is. The kinetic energy? This converts to 3.52x10^-19 J Rest mass...
  29. E

    Does energy level determine the smallest region of spacetime that can be probed?

    Is it true that as you go higher in energy, from 1 eV to GeV to 10 TeV, you can probe smaller spacetime region. Since the LHC has only probed up to the 4 TeV or so, it means they have probed the corresponding tiny region of spacetime.. meaning it is still possible spacetime becomes discrete at...
  30. marellasunny

    Calculation of the battery pack voltage for an EV

    I'm a Automotive engineer and hence lack the electrical engineering expertise that you might expect. This is related to a doubt I have in calculating the final battery voltage for an electrical vehicle. This is just a calculation query. I have a module consisting of 12 individual Li-ion cells...
  31. G

    EV and Decision Making: How Utility Functions Impact Our Choices

    So, I'm having a pretty lazy day and decided to do some thinking. And, while this usually turns out to be a splendid idea, today it resulted in me hurting myself. Psychically. So yeah. I've been through a lot of toy games trying to figure out a way to reconcile this all in my brain box, but...
  32. T

    Bohr Model of the Hydrogen atom: Prove that Eo = 13.6 eV

    Homework Statement Verify that the equation of the ground state energy Eo of the Bohr atom: Eo= (2pi2e4mek2)/h2 simplifies to Eo = 13.6 eV. Show clearly how the units of the different quantities in the equation simplify to the eV. This is all they give. Nothing more...
  33. U

    EV vs V, Cutoff Potential Question

    Homework Statement Light with a wavelength of 630 nm is directed at a metallic surface that has a work function of 1.5 eV. Find a) the maximum kinetic energy of the emitted electrons b) the cutoff potential required to stop the photoelectrons Homework Equations Ek = [(h * c) / λ] -...
  34. D

    When is it safe to use eV units and when do we have to convert eV units into kg?

    Homework Statement I have a misunderstanding of when I can safely use eV units in a formula. For example in the formula p = \sqrt{\frac{E^{2} - m^{2}c^{4}}{c^{2}}} I can put the energy and mass in terms of MeV and get an answer with units MeV/C, which makes sense. But then there was this...
  35. Z

    Ramsauer-Townsend equation. Joules or eV?

    Homework Statement There is a Ramsauer-Townsend equation in my notes for transmission. It's difficult to write out but looks somewhat like: T = {1 + {(sin k a)^2 / 4E/V0 (E/V0 - 1)}} Of course E and V0 should be in the same units. But should they both in Joules or eV? I would...
  36. T

    Parimutuel market: maximize your EV

    Your coworkers are competitive people who like to gamble. They have set up a bet pool on the longest run of heads (call this R) that occurs in a sequence of 100 fair coin flips. In this pool you are allowed to bet on any combination of three mutually exclusive outcomes: 1) R < 6 2) 6 <= R <...
  37. R

    Converting eV to V: Debunking the Myth and Simplifying the Process

    I've done some research on this, but some people say that you cannot convert these two things. They say that V is electric potential, and eV is energy. What I was thinking was since eV = Q[SUB]electron[SUP] * V, can't you just divide eV by charge of electron to get V? Sorry if this is a...
  38. P

    How Does Converting eV to Joules Work?

    Hi, I know that the definition of eV is the energy gained by one electron accelerated through one volt: (E = Vq) And I therefore believe we can define the Joule as the energy gained by one coulomb of charge accelerated through one volt. To convert eV to joules, all we would have to do is...
  39. L

    Calculating Energy Levels in an Infinite Potential Box: Converting to eV?

    Homework Statement well the problem is electron moving in an infinite poentail box of dimensions... calc all posible energy level in (eV) Homework Equations E=h2/8M(nx2/a2+... The Attempt at a Solution ok so no idea how they get h2/8M to = 37.6 h is planks constant the units are...
  40. O

    Why is plasma frequency in ev and not hz

    Why is the plasma frequency and the relaxation frequency expressed in eV instead of Hz? eV is a measurement of energy, not frequency. What is the plasma frequency, relaxation requency and Debe length, and how are they all related? Thanks, Ninja
  41. BWV

    Correct units to derive Ryberg Constant in ev

    Putting together a spreadsheet to calculate the hydrogen spectrum, cannot seem to get the right mix of units to get the Rydberg constant of 13.605... eV also, what is the significance of R (1/n^2-1) converging to R as n gets large? can anyone put this together or refer me to a source that...
  42. J

    What units are used after eV, MeV, GeV, etc, are divided by c^2?

    I know that the mass of subatomic particles is usually given in electronvolts, and that c^{2} is set to 1 so that we can say, "This particle has a mass of 13 eV." However, if you divide 13 eV by c^{2}, you get an answer, x. What units is this in? Oh, also, what units do we use c in in the...
  43. T

    Potential Difference of 1200 V Gives Electron 1200 eV Kinetic Energy

    An electron is accelerated from rest through a potential difference 1200 V. Give the electron's kinetic energy after this acceleration in electron-volts? ----I know the answer is 1200 eV but if someone could explain how to get the answer?? And how do I apply 1/2mv^2=qV
  44. D

    Question: eV level of orbiting electrons

    I've been reading of the Bohr model lately and I was wondering...do we only know the energy levels of electrons orbiting hydrogen or do we know these levels for other atoms? If not, is there a way to calculate this using the Shrodinger or is this just part of the whole mystery? Thank you for...
  45. R

    Calculating Battery requirements for EV

    I have a motor which i am planning on using in an electric vehicle i am designing. http://www.azuredynamics.com/products/force-drive/documents/AC24_DMOC445ProductSheet.pdf and want calculate the number and specs of batteries needed to run it. I have the power demand from the motor at...
  46. X

    Kinetic Energy (in eV) of He with given change in potential

    Homework Statement Point A is at a potential of +230 V, and point B is at a potential of -140 V. An -particle is a helium nucleus that contains two protons and two neutrons; the neutrons are electrically neutral. An -particle starts from rest at A and accelerates toward B. When the -particle...
  47. J

    Planck's Constant Conversions: J s to eV s

    So, my physics final is tomorrow, and for the test we are given a list of constants. On this list is Planck's constant as 6.626x10^-34 J s. Now, that's all well and good, but they don't give it to us in eV s! And we need it in eV s for some of the problems. Given that we also get...
  48. L

    Converting V to eV: A Problem Solving Guide

    Homework Statement How can i convert V to eV in a problem? I know that 1V=1.6X10^-19 J but I don't see how that can help... Thanks.
  49. L

    Solve de Broglie Wavelength of Atoms in eV: Urgent Help

    Homework Statement http://www.strings.ph.qmul.ac.uk/~russo/QP/r06QPHYEX.pdf Question 3. The Attempt at a Solution I can easily derive the equation I need, which is: lamda = h/p Which after some playing around with K.E =1/2mv^2 etc we obtain: lambda (de brogile) = h/SQRT(2mKE)...
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