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EV to J

  1. Feb 28, 2005 #1
    how do u convert eV to joules again?
     
  2. jcsd
  3. Feb 28, 2005 #2

    Integral

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    some google key works "conversion factor" "ev" "power".

    Why do you expect me or someone else to do your basic web search?
     
  4. Mar 1, 2005 #3
    Googling "eV" gives it out directly :

    1 electron volt = 1.60217646 × 10-19 Joules
     
  5. Mar 1, 2005 #4

    dextercioby

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    Actually it's not basic web search.It would really be a shame to search the web for eV->J conversion factor...:yuck:

    Daniel.
     
  6. Mar 1, 2005 #5

    Integral

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    Why is that dex?
    Not everyone has reference at hand. My goal was perhaps to lead him to a page full of conversion factors. Unfortunatly he may well find a calculator for doing conversions, and therefore never learn to do it on his own. But I think a web search is perfectly fine for this.
     
  7. Mar 1, 2005 #6

    dextercioby

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    Depends on the OP's intentions.If he's aiming to become a physicist (which may vey well not be the case),then it's a shame not to know THIS SPECIFIC CONVERSION...
    I'm not talking about-psi->torr->pascals,but eV->J...:wink:

    Daniel.
     
  8. Mar 1, 2005 #7
    99.99% students in a highschool physics course are not going to be physicists, and,
    99.9% students in a college physics course are not going to be physicists
     
  9. Mar 1, 2005 #8
    I don't think that's quite right.

    What's the percentage of high school/college students who go on to do a Physics degree?
    In mine it must have been about 5% or a bit under.
    My definition of physicist is someone who qualifies to at least degree standard.
     
  10. Mar 1, 2005 #9
    what school are you in.... in my university.... out of 40000 student.... only 20 or so will graduate in physics this year!
     
  11. Mar 1, 2005 #10
    I got to agree with vincentchan. A University I know has the same ratio. And that's not counting the significant amount of people who do not go to Univ. at all after school.

    But back to the point, anyone who knows what an eV is should probably know the number 1.602E-19, at least 1.6E-19, but perhaps not the following decimals.
     
  12. Mar 1, 2005 #11

    dextercioby

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    Since the second decimal is zero,it's useless to memorize 4 significative digits.An error made by neglecting that 4 decimal is much smaller than working with other constants,like \hbar...

    Daniel.

    P.S.I hope i made my point clear.
     
  13. Mar 1, 2005 #12
    What controversy!

    I think the most useful way to know this is realize that an eV is by defintion the work done moving an electron through one volt - i.e., since 1C * 1V = 1J, and the charge of an electron is 1.602x10^-19J...
     
  14. Mar 1, 2005 #13

    dextercioby

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    That's not a correct "defintion" (sic).Please do not supply erroneous information...

    Daniel.
     
  15. Mar 1, 2005 #14

    Galileo

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    What's erroneous about it?
     
  16. Mar 1, 2005 #15

    dextercioby

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    One "eV" is the energy that an electron gets when accelerated from rest by a potential difference of 1V.

    Daniel.

    P.S."moving an electron" sounds obscene.It's like moving furniture...:yuck:
     
  17. Mar 1, 2005 #16

    krab

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    Not true, and even if it were true, not relevant. Are you proposing that physics teaching standards can be lower because of the unlikelihood of producing physicists? Seems backwards to me.
     
  18. Mar 1, 2005 #17

    chroot

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    It doesn't matter whether or not the electron was initially at rest.

    If you move an electron through a potential difference of 1V, the electron gains (or loses) 1 eV of kinetic energy.

    - Warren
     
  19. Mar 2, 2005 #18
    I'm getting off topic, but do you have any contradicting stats?
     
  20. Mar 2, 2005 #19

    dextercioby

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    Does Vincentchan have contradicting stats for Krab's affirmation...?:bugeye:

    Anyway,for the record,i think Krab is right.

    Daniel.
     
  21. Mar 2, 2005 #20
    2 stats to 0 stats. Eager for more numbers, and completely open minded.
     
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