# Homework Help: The speed at which a proton strikes the positive plate (uniform electric field).

1. Dec 11, 2012

### _Chemicals_

1. The problem statement, all variables and given/known data
Here is the problem given. The answer is E.

2. Relevant equations

No equations are given. Assumed use of standard equations for electric field and force involving electric field.

3. The attempt at a solution
I tried using a few equations (E = F/q0), (F = mv^2), (E=(1/(4piEp0))(q/r^2)), and solving, but no luck. Could someone please give me guidance?

2. Dec 11, 2012

### Staff: Mentor

If you can determine the force F acting on the charge, and this force acts on the proton over a distance of 7 cm, how much work is done?

3. Dec 11, 2012

### _Chemicals_

Alright so I just remembered the simple equation F = qE so now I'm going to attempt what you said. Physics is not my strength however, so I will probably be back.

4. Dec 11, 2012

### Staff: Mentor

No worries, we'll be here!

5. Dec 11, 2012

### _Chemicals_

Thank you for your tip. I was able to solve it!

6. Dec 11, 2012

Excellent.