Electron and parallel plate question >

AI Thread Summary
An electron enters a cathode ray tube with an initial horizontal velocity of 4.8x10^7 m/s and is subjected to an upward electric field of 3.70x10^4 N/C between parallel plates. The electric field causes a downward acceleration on the electron, while its horizontal velocity remains constant. To solve for the distance the electron falls before striking the screen, one must calculate the acceleration from the electric field, determine the time it takes to travel the horizontal distance, and then use this time to find the vertical displacement. The problem assumes the neglect of fringing fields at the entry and exit of the plates. Understanding the relationship between electric field intensity and force on the electron is crucial for solving the problem.
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electron and parallel plate question >:(

Homework Statement


The diagram below shows an electron entering the region between the parallel plates of a cathode ray tube. The electron has an initial velocity of 4.8x10^7 m/s horizontally and enters the exact middle point between the plates. The electric field intensity between the playes is 3.70x10^4 N/C upward. How far below the point midway between the plates will the electron strike the screen at point P?

http://img246.imageshack.us/img246/9690/26772065aj1.jpg
http://g.imageshack.us/img246/26772065aj1.jpg/1/

Homework Equations



This is my first time trying this and I have no clue how to approach this questions. Could someone direct my in the right way please?
 
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Electron behaves like a projectile.Since the direction of the electric field is upwards, the horizontal velocity remains the same. Electric field accelerates the electron in the downward direction. Find the acceleration. Range is given. Find the time taken by the electron to reach the screen. Knowing the acceleration and time find the distance traveled by the electron in the down ward direction.
 


The units of Electric Field are V/m, so that should give you a hint for how to calculate the E-Field between the plates. Then, there is an equation for the force on an electron, based on the E-Field. That (constant) force acts for the whole time the electron is flying between the plates...

BTW, this question presumably tells you to ignore the fringing field at the entry and exit of the plates...
 


Ack, rl.bhat was too quick for me!
 

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