The work done by an electric field in accelerating a charged particle?

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Homework Help Overview

The discussion revolves around a charged particle accelerating in a uniform electric field between two plates. The problem involves calculating force, work done, changes in kinetic energy, and potential energy related to the particle's motion.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • The original poster attempts to calculate the force on the particle and the work done by the electric field, expressing uncertainty about the equations used for parts B and C. Some participants confirm the correctness of the original poster's calculations and suggest that the change in potential energy relates to the gain in kinetic energy.

Discussion Status

Participants have confirmed the calculations for parts A, B, and C, while discussing the relationship between potential energy and kinetic energy. There is ongoing exploration regarding the change in potential energy and its connection to the work done on the particle.

Contextual Notes

There is a mention of conservation of energy principles in the context of potential and kinetic energy changes. The original poster expresses uncertainty about the validity of their answers and the appropriate equations to use.

Dongorgon
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Homework Statement


A particle with a charge of 3.2x10^-19 C accelerates from rest between two charged plates. The electric field is uniform and is 39000 N/C. The distance between the plates is 4.5x10^-3 m.

A) Calculate the force on the particle
B) How much work is done by the electric field in accelerating the particle between the two plates?
C) What is the increase in kinetic energy of the particle?
D) What is the change in potential energy of the particle?

Homework Equations



My answers so far:

A) Using F=QE to get an answer of 12fN

B) I'm not sure on the validity of this answer, or infact the right equation to use for this question and parts B and C.

I've used WD = FxD
Therefore, an answer of 56.2 aJ

C) Would the increase in kinetic energy be simply the change in energy experienced for part B)?

Any help would be greatly appreciated!
 
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A) correct!
B) correct!
C) You are right!
D) The change in P.E. will be equall to minus the gain in K.E. (conservation of energy)
 
cosmic dust said:
A) correct!
B) correct!
C) You are right!
D) The change in P.E. will be equall to minus the gain in K.E. (conservation of energy)

So both part B and C have the same answers of 56.2 aJ?

For D would the answer be along these lines?

25iss5w.png
 
Dongorgon said:
So both part B and C have the same answers of 56.2 aJ?

For D would the answer be along these lines?

25iss5w.png

Since the particle acquires a P.E. because of the work done on it and this is converted to K.E., so the answer to (D) is << solution deleted by Mentor -- but use his hint to fix your answer... >>
 
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