Electric Potential Difference involving Alpha Decay question

AI Thread Summary
The discussion revolves around calculating the minimum electric potential difference required to bring an alpha particle to rest after alpha decay of a plutonium-239 nucleus into a uranium-235 nucleus. The user has attempted to derive the mass difference and energy using the mass-energy equivalence formula, but is uncertain about their approach. They question whether to use kinetic energy formulas instead and express confusion about the implications of electric potential in this context. The calculations provided yield an extraordinarily high voltage, prompting concerns about the accuracy of the method used. Clarification on the correct approach to solve the problem is sought, emphasizing the importance of understanding the relationship between energy, charge, and potential difference in nuclear decay scenarios.
Eloc Jcg
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Homework Statement


A plutonium-239 nucleus, initially at rest, undergoes alpha decay to produce a uranium-235 nucleus. The uranium-235 nucleus has a mass of 3.90x10^-25 kg, & moves away from the location of the decay with a speed of 2.62x10^5 m/s. Determine the minum electric potential difference that is required to bring the alpha particle to rest.


Homework Equations


V = ? = E/q
E = mc^2
m = mparent - mproducts
q = elementry charge x #protons

The Attempt at a Solution


m = 239.052156u - 235.0439299u - 4.002603u = -0.9943769u
E = -0.9943769u x 3x10^8m/s = 8.9493921x10^16 eV
q = 1.6x10^19C x 92protons = 1.472x10^-17 C

V = 8.9493921x10^16eV / 1.472x10^-17C = 6.08 x 10^33 V

Am I way off here in my approach to solving this problem? Or should this problem be solved using the Ek = 1/2mv^2 formula? Any help is appreciated as this is my last assignment I am needing to do, which assuming I pass my final, I will be done high school. I've been up all night working on this problem, & flipping through my high school physics textbook & my college electronics textbook, but I am not sure what to expect as my final answer.

Thanks.
 
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I was thinking maybe use the F = E q = Vq/d = ma ?
But that means any non zero potential will be able to bring it to rest (lower potential will simply take long to do it and the nucleus will travel a larger distance while decelerating).
 
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