Electrostatic potential and velocity

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SUMMARY

The discussion centers on calculating the velocity of an electron moving from point B to point A, where point A has an electrostatic potential of +1V. The energy of the electron is established as 1 eV, equivalent to 1.6E-19 Joules. The participant initially misapplies the equations for potential energy (PE) and kinetic energy (KE), leading to an incorrect conclusion of zero velocity. Correcting for the electron's negative charge is essential for accurate calculations.

PREREQUISITES
  • Understanding of electrostatic potential and its relation to energy
  • Familiarity with the concepts of kinetic energy (KE) and potential energy (PE)
  • Knowledge of the electron volt (eV) as a unit of energy
  • Basic algebra for solving equations involving velocity
NEXT STEPS
  • Review the principles of electrostatics and potential energy calculations
  • Study the relationship between electric potential and kinetic energy in charged particles
  • Learn about the concept of electron volts and their applications in physics
  • Practice solving problems involving the motion of charged particles in electric fields
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Students studying physics, particularly those focusing on electromagnetism and energy conservation, as well as educators looking for practical examples of electrostatic potential calculations.

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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 definition 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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