# Electric Field Problem

1. Feb 4, 2008

### desibabu90

[SOLVED] Electric Field Problem

1. The problem statement, all variables and given/known data

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?

2. Relevant 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)

3. The attempt at a solution

2. Feb 4, 2008

### Shooting Star

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.

3. Feb 4, 2008

### desibabu90

thanx a lot for helping me out

it worked!!!