Simple electric field strength problem

AI Thread Summary
To find the distance from a 360μC charged particle where the electric field strength is 49mN/C, the relevant equation is E = (8.99 x 10^9) x (Q/r^2). The user attempted to rearrange the equation to solve for r but arrived at an incorrect value of 8127. The expected answer is 186mm, leading to confusion about the accuracy of the provided solution. Clarification on the calculation steps and potential errors is needed to resolve the discrepancy.
liamporter1702
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Homework Statement



How far away from a 360μC charged particle is the electric field strength 49mN/C?

Homework Equations


E=(8.99x10^{9} x \frac{Q}{r^{2}}

The Attempt at a Solution


I assumed it would be a simple case of rearranging the equation to give r=\sqrt{\frac{8.99x10^{9}xQ}{E}} but after doing this and subbing in the values I got a value of 8127, which is clearly not correct. The answer that has been given is 186mm but I can't see the solution.
 
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Could it be a case of the answer given is not correct?
 

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