How Do You Calculate the Force Needed to Accelerate an Electron?

[crimsonn]

Homework Statement

use the work energy theorem to find the force required to accelerate an electron (m=9.11 X10^-31 kg) from a speed of 1.50 X10^7 m/s in a distance of .0125

Homework Equations

W=Fd KE= 1/2mv^2

W=KE

The Attempt at a Solution

I've tried this problem about eight times, and each time I managed to get a different answer, but this is my try at a solution

W=Fx
W/x= F

W=1/2mv^2

mv^2/2x = F

however, this does not work for me.

the answer is 3.56 X10 -19N

 

[Rake-MC]

Homework Statement

use the work energy theorem to find the force required to accelerate an electron (m=9.11 X10^-31 kg) from a speed of 1.50 X10^7 m/s in a distance of .0125

[...]

To a speed of what? What is the unit of distance?

 

[merryjman]

Yeah, was this electron at rest to begin with, or was it in motion already? Check the wording of your question.