What Is the Speed of an Electron With 100000 eV Kinetic Energy?

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The discussion centers on calculating the speed of an electron with 100,000 eV of kinetic energy using relativistic equations. The initial attempt yielded a velocity of 0.9 x 10^8 m/s, while the textbook states the correct answer is 1.6 x 10^8 m/s. The user is self-studying for a physics olympiad and is encountering relativity for the first time. It is suggested that the error lies in the numerical evaluation rather than the method used. The user plans to re-evaluate their calculations to find the correct speed.
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Homework Statement


what is the speed of an electron with kinetic energy of (a) 100000 eV

Homework Equations


m=m0/√(1-β2)
K=Δmc2

The Attempt at a Solution


plug first into second equation, isolate v and it eventually comes out to be
v=c(1-(1+K/m0c2)-2)
plug in numbers and i get a velocity of 0.9*108 m/s
the answer is 1.6*108 m/s in the textbook.

Note: This isn't a school assignment. I am self studying for physics olympiad, and this is my first encounter with relativity from a mathematical stand point.
 
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Your method is correct. So, the mistake must be in plugging in the numbers and evaluating.
 
will try again, thanks
 

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