Velocity and momemtum of 10 Mev Electron

Thread starter madjens
Start date Sep 22, 2008
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Electron Velocity

AI Thread Summary

The discussion revolves around calculating the velocity and momentum of an electron with a rest mass of 0.511 MeV and a kinetic energy of 10.0 MeV. Initial calculations using the formula sqrt(2KEm) resulted in an impossible velocity exceeding the speed of light. Another approach involving the equation Rest E + KE = sqrt(m^2c^4 - p^2c^2) led to a negative root, indicating a miscalculation. Ultimately, the original poster resolved the issue but did not specify the correct method or final results. The conversation highlights the complexities of relativistic physics in particle momentum and energy calculations.

Sep 22, 2008

madjens

Homework Statement

Find the velocit y and momentum of an electron (rest mass of 0.511MeV) with a
kinet ic energy of 10.0 MeV.

The Attempt at a Solution

The momentum I calculate using sqrt(2KEm) is giving me a V larger than the speed of light. This can't be true.

If I try
Rest E + KE = sqrt (m2c4 - p2c2) it gives me a negative root.

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Sep 22, 2008

madjens

Nevermind, I figured it out.

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