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Homework Help: Question on nuclear/quantum mech. unit of physics, please help its due 10pm tonight

  1. May 2, 2010 #1
    energy from electron passing between 2 electrodes, and calc. the freq of the elec.

    1. The problem statement, all variables and given/known data
    Part 1:
    The difference in potential between the cathode and anode of a spark plug is 17800 V.
    What energy does the electron give up as it
    passes between the electrodes?
    Answer in units of J.

    Part 2:
    One fourth of the energy given up by an electron is converted into radiation in the form of
    a single photon.
    What is the frequency of the radiation?
    Answer in units of Hz.

    2. Relevant equations
    v=i*r?
    Q = Δmc2
    E=hf?
    planck's constant=6.62607 × 10^-34 J · s
    c² =931.5 MeV/u
    1 eV=1.602×10−19 J
    idk what else is needed sry

    3. The attempt at a solution

    I'm not sure how to begin this problem, but my attempts are listed below
    Pt.1: E= (1.602×10−19 J)(17800V)=2.85156 x 10^-15
    Pt 2: E=hf
    [(1/4)*(2.85156 x 10^-15)]/(6.62607 × 10^-34 J · s) =f <<<<-not sure
    f=1.075886612 x 10^18 Hz??
     
    Last edited: May 2, 2010
  2. jcsd
  3. May 2, 2010 #2
    Re: question on nuclear/quantum mech. unit of physics, please help its due 10pm tonig

    never mind i got it answered
    turns out my process was correct
     
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