Electrostatics Questions

1. Jan 24, 2006

music_man05

Answers or Steps, or even formulas are welcome, Any answer to any of them!
Okay First qusetion...

A proton is placed in an electrical field that counters the effect of gravity at sea level. Find The Electric Field.

Second Question...

A Proton is accelerated from rest in an electric field of 500.0 N/C. Find the velocity and kinetic energy of the proton at 3.00x10^-5s.

And Last Problem....

Three +1.00 uC charges are placed in the corners of a rectangle. height 2cm and width 10cm. Find the electric field at the forth unoccupied corner.

Last edited: Jan 24, 2006
2. Jan 24, 2006

StatusX

Any ideas? You have to at least show an attempt to do the problems before you'll get any help.

3. Jan 24, 2006

music_man05

OK here is where I am at

For the first question All I can think of is the formula Fg = Fq then mg=qE then E = mg/q and q = 1e is that correct??

For the second one I have just KE = 1/2mv^2 E = 500N/C E = Fe/q = Kq/r^2

and for the third one I have Nothing, I don't even know where to start...Maybe I just need a starter for it or give me a formula

4. Jan 24, 2006

StatusX

\begin{align*} \vec E &= \frac{k q}{|r|^2} \hat r \\ &= \frac{k q}{|r|^3} \vec r\end{align*}
\begin{align*} E_x &= \frac{k q}{|r|^3} r_x \\ &= \frac{k q}{(\Delta x^2+\Delta y^2)^{3/2}} \Delta x \end{align*}