Electron displacement between two parallel plates

[SoundZombie]

The problem is attached, stuck on part d.

Homework Statement

Im given a problem with two horizontal and parallel plates 8cm long 3cm away from each other. An electron is moving through them with a velocity V_{0}. It is also given that the voltage across the plates is 20 Volts and the electron deflects upwards 1.2 cm.

Homework Equations

Ive done all the work for parts a, b, and c, which gave me a F_{electric} of 666.67 V/m or 666.67 N/C down, and an acceleration of 1.17 * 10^{14} m/s^{2} up.

The Attempt at a Solution

I have no idea how to even come at this. The only idea I had without being given an initial velocity in any direction is something with the deflection of 1.2 cm, but I don't know how to use that without knowing the amount of time the electron spends between the plates.

Thanks for ANY help.

 

[gneill]

The problem is attached, stuck on part d.

Homework Statement

Im given a problem with two horizontal and parallel plates 8cm long 3cm away from each other. An electron is moving through them with a velocity V_{0}. It is also given that the voltage across the plates is 20 Volts and the electron deflects upwards 1.2 cm.

Homework Equations

Ive done all the work for parts a, b, and c, which gave me a F_{electric} of 666.67 V/m or 666.67 N/C down, and an acceleration of 1.17 * 10^{14} m/s^{2} up.

The Attempt at a Solution

I have no idea how to even come at this. The only idea I had without being given an initial velocity in any direction is something with the deflection of 1.2 cm, but I don't know how to use that without knowing the amount of time the electron spends between the plates.

Thanks for ANY help.

Hello SoundZombie. Welcome to Physics Forums.

You've calculated an acceleration for the electron in the vertical direction, and you're given the vertical deflection that it experiences over its time between the plates. What can you make from that? What kinematic equation might apply?

 

[SoundZombie]

Hello SoundZombie. Welcome to Physics Forums.

You've calculated an acceleration for the electron in the vertical direction, and you're given the vertical deflection that it experiences over its time between the plates. What can you make from that? What kinematic equation might apply?

I knew I was overlooking something small. haha

d_{y}=v_{0y}t+1/2a_{y}t^{2} which will end up being 1.2cm=(0)t+(1/2)(1.17*10^{14}m/s^{2})t

Im still having a little trouble remembering all of these because I took Physics 1 about 4 or 5 years ago, and I am just taking Physics 2 now. I am trying to re-learn everything at once. Thanks for the quick reply. Youre a life-saver!