# Is this how to attempt this problem on electric field strength

1. Mar 30, 2016

### KieranRC

1. The problem statement, all variables and given/known data
Two parallel plates at -50kV and 100kV have separation 35cm. a proton is placed between the plates. calculate the electric field strength between the plates

2. Relevant equations
E=v/d

3. The attempt at a solution
100kV--50kV=150kV 150x10^3/0.35=428571.4N/C

2. Mar 30, 2016

### BvU

Hello Kieran,

In one word: yes !

(However, since you only get two digits from the voltage, perhaps 420 $\times 10^3\$N/C is a bit cleaner. But by all means: do further calculations with the number you found.)

3. Apr 4, 2016

### KieranRC

Okay, great! Thank you

The question later goes on to ask what force is experienced by the proton and i really dont know where to start on this one, could you try shed some light on this for me? Thanks

4. Apr 4, 2016

### BvU

For that you need a relevant equation, something like Force = Electric field strength * charge, or $\vec F = q \vec E$. You have the two factors on the right, so: no problemo. But check the direction !