How Does an Electric Field Affect Electron Motion?

AI Thread Summary
An electric field exerts a force on an electron, resulting in acceleration calculated using the formula a = (e/m)E, yielding an acceleration of -2.45E13 m/s². The electron's x-component of velocity remains constant at 1.5E5 m/s while the y-component is influenced by the electric field. To find the electron's velocity after it has moved 3.6 cm in the x-direction, kinematic equations are applied, considering both the initial velocity and acceleration. The time for the x displacement is easily determined since the x velocity is constant. The discussion concludes with successful application of these principles to solve the problem.
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[SOLVED] Electric Field Problem

Homework Statement



At some instant the velocity components of an electron moving between two charged parallel plates are Vx = 1.5E5 m/s and vy = 1.8E3 m/s. Suppose that the electric field between the plates is given by E = (140 N/C) j.

(a) What is the electron's acceleration in the field?

(b) What is the electron's velocity when its x coordinate has changed by 3.6 cm?

Homework Equations


I got the first answer doing ---- a = (e/m) E.

so the answer came out to be -2.45E13.

For b. you have to find the x portion for the velocity and the y portion of the veloctity

i found the x, it just stays the same and for the y:

Kinematics:

D = v0^2 - v^2 / (2a)

2aD = V0^2 - V^2

V = sqrt(v0^2 + 2aD)

The Attempt at a Solution


V = sqrt(v0^2 + 2aD)


Please help
 
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Find the time 't' for the x to change by 3.6 cm, which is easy since vx is constant.

For motion in y dircn, initial speed v_yi is given, the accn in y dircn you know, and so apply v_yf = v_yi + at.
 
thanx a lot for helping me out

it worked!
 
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