Electric Fields Question, What is the speed of the electron?

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SUMMARY

The discussion focuses on calculating the speed of an electron released in a weak electric field of -2.8 x 10^-10 N/C after traveling a vertical distance of 1.9 µm, while considering gravitational force. Key equations include E=F/q, F=qE+qV*B, and Work Done = F*d = 1/2(mv^2). The user attempted to apply these formulas but encountered difficulties, indicating a need for clarification on the correct approach to incorporate both electric and gravitational forces in the calculation.

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  • Understanding of electric fields and forces, specifically E=F/q
  • Knowledge of gravitational force and its impact on charged particles
  • Familiarity with kinematic equations and energy conservation principles
  • Basic proficiency in using the Flipit Physics platform for problem-solving
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  • Review the concept of electric fields and how they affect charged particles
  • Study the derivation and application of the Lorentz force equation F=q(E+v*B)
  • Learn how to combine forces in motion problems, particularly with gravitational effects
  • Practice similar problems using the Work-Energy theorem to find velocity
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This discussion is beneficial for physics students, educators, and anyone seeking to understand the dynamics of charged particles in electric fields, particularly in the context of homework or exam preparation.

Rangers1994
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Homework Statement


An electron is released from rest in a weak electric field given by -2.8 x 10^-10 N/C [PLAIN]https://www.flipitphysics.com/Content/smartPhysics/Media/Images/Tipler/Symbols/jhatbold.gif. After the electron has traveled a vertical distance of 1.9 µm, what is its speed? (Do not neglect the gravitational force on the electron.) Answer should be in mm/s.

Any help towards setting up this problem or what formula to use will be greatly appreciated.

Homework Equations


E=F/q
F=qE+qV*B

F= (1/4πE0)(q1q2/r^2)
Fnet=Fg=ma=mg

Work Done = F*d = 1/2(mv^2)

The Attempt at a Solution


I don't really know where to start, this is the last problem on my assignment and I only have a few attempts left, we did not go over this in class yet and our class uses "Flipit Physics" videos instead of a book.

I tried Fe=qE
=(1.602x10^-19)(-2.8x10^-10) = -4.4856x10^-29
then a = Fe/m
= -4..572477064 x 10^-31 which was wrong

I also tried Work Done = F*d = 1/2(mv^2) and solved for v but that was also wrong.
 
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E=1/2mv^2 is equal to the total work done on the particle. You have two forces: the Lorentz force F=q(E+v*B) and gravitational force F=mg, both in the same direction (I assume j-hat is the unit vector in the y direction).
 

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