The discussion centers on determining the position of a proton required to generate an electric field of <0, 5e4, 0> N/C at the origin <0, 0, 0>. The relevant equation used is \(\vec E = \frac{q\hat{r}}{4\pi\varepsilon r^2}\). Participants clarify that \(\hat{r}\) is a unit vector indicating direction, and the magnitude \(r\) was calculated as approximately 1.69707e-7 meters. However, confusion arises regarding the correct placement of the proton to achieve the desired electric field.
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cowmoo32 said:Homework Statement
You want to create an electric field = < 0, 5e4,0 > N/C at location < 0, 0, 0>.
Where would you place a proton to produce this field at the origin?
Homework Equations
\vec E = q\hat{r} / 4\pi\varepsilon r^2
The Attempt at a Solution
I'm not sure how to treat \hat{r} in the equation. Obviously, I know it's equal to r/rmag, but rmag is what's throwing me.
That's just a unit vector (magnitude = 1) giving the direction of the field. The field from a positive charge is radially outward.cowmoo32 said:I'm not sure how to treat \hat{r} in the equation. Obviously, I know it's equal to r/rmag, but rmag is what's throwing me.
cowmoo32 said:Ok, I thought that unit vector might be 1, so I solve for r^2, correct? I tried that and didn't get the right answer.
cowmoo32 said:5e4 = [(1.6e-19)(9e9)] / r^2
I got r = 1.69707e-7
cowmoo32 said:Because when I submit it online it tells me that's the wrong answer. I'm not sure what I'm doing wrong.