Kinetic energy from plate A to plate B

AI Thread Summary
An electron gains 3.45x10^(-16) J of kinetic energy when moving from plate A to plate B in an electric field. The calculated potential difference between the plates is 2.16x10^3 V, indicating that plate B is at a higher potential. The relationship between kinetic energy and potential energy is crucial, as the energy conversion occurs due to the electric field. The electron is attracted to the positive plate, which has a higher potential compared to the negative plate. Understanding the conservation of energy is essential in analyzing the potential energy of the electron at plate A.
hanna.eunice
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Homework Statement


An electron acquires 3.45x10^(-16) J of kinetic energy when it is accelerated by an electric field in a computer monitor from plate A to plate B. What is the potential difference between the plates, and which plate is at the higher potential?


Homework Equations


KE=1/2mv^2


The Attempt at a Solution


The given answer is 2.16x10^3V...How and why?
Plate B has the higher potential.
 
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What is the potential energy of the electron at plate A?
 
Nothing is given other than the acquired electron energy of 3.45x10^(-16). Sorry!
 
Would the electron be attracted to a positive plate or a negative plate? Which plate (positive or negative) would have a higher potential?

Conservation of Energy: All the electric potential will be converted to kinetic.
 
hanna.eunice said:
Nothing is given other than the acquired electron energy of 3.45x10^(-16). Sorry!

That is correct, but the electron still has some potential energy. How is it related to the difference of the plates' potentials?
 
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