What Is the Correct Electric Field Calculation for a Point Charge?

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The correct electric field calculation for a point charge of 2 x 10^-9 C at a distance of 10 cm is determined using the formula E = kq/r^2. Applying this formula, the electric field is calculated to be 1800 N/C. The initial calculation mistakenly included an extra unit, leading to confusion regarding the answer. The correct approach clarifies that the electric field, not voltage, is the focus. Thus, the correct answer is 1800 N/C.
nautica
The electric field at a distance of 10 cm from an isolated point charge of 2 x 10^-9 C is:

A)1.8 N/C
B)180 N/C
C)18 N/C
D) 1800 N/C
E)none of these

This is the formula I used Q=rv/k

so (2x10^-9 C)(9x10^9 Nm^2) / .1 m C^2

I am getting 180 N m/C - I have an extra m in the equation, which would make it none of the about. Evidently I am doing something wrong.

Thanks
Nautica
 
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E = \frac{kq}{r^2}
 
You want E, not V.

For a point charge:

E = kq/r^2
 
1800 N/C, thanks, nautica
 
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