Electrostatic potential and velocity

AI Thread Summary
An electron moves from point B at 0V to point A at +1V, gaining energy in the process. The energy gained is equivalent to 1 electron volt (1.6E-19 Joules). The initial attempt at solving the problem incorrectly assumed the potential energy equation, leading to a conclusion of zero velocity. Clarification is needed regarding the electron's charge, which is negative, affecting the calculations. Correctly applying the equations will yield the proper velocity for the electron as it moves to the higher potential.
ryukyu
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Homework Statement



Point A is at an electrostatic potential of +1V relative to point B in a vacuum. An electron initially at rest at B moves to A. What is its velocity in m/s?

Homework Equations



E = PE + KE
PE= J/q * q
KE = 0.5 mv^2 (where v = velocity)

The Attempt at a Solution


Based on the definiton of an electron volt (eV), the energy of the electron is 1eV or 1.6E-19 Joules.

In solving the first equation:
1.6E-19 J = 1 J/C * e- + 0.5mv^2
e-= 1.6E-19C
based on my error (whatever that may be)
0 = 0.5mv^2 which means v=0, this doesn't seem correct.

Any suggestions?
 
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Shouldn't the charge of the electron be negative? Then you'd end up with

2x=.5mv^2

Where x is the 1.6*10^-19...
 


Thanks,

I knew it was something simple that I had missed.
 

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