(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A -14.1 nC charge is located at position (x,y) = (2.48 cm, 1.24 cm). At what (x,y) position is the electric field -262600.0i? (Enter your x position first followed by the y position.)

2. Relevant equations

E = kQ/r^{2}

E = electric field strength

k = 9 x 10^{9}

r = distance to the point from the charge

3. The attempt at a solution

E = kQ/r^{2}

∴ r = √(kQ/E)

r = 0.02198

original position: (0.0248m, 0.0124m)

electric field: -262600.0i,

unit vector 'i' indicates only x component, no y component:

therefore y component is the same (electric field vectors go straight in toward -'ve charge)

therefore x-component is..

0.0248 + r

=0.0248 + 0.02198

= 0.04678m

final answer:

(0.04678m, 0.0124m)

Originally what I did was

0.0248 - r

=0.0248 - 0.02198

= 2.82E-3

final answer:

(2.82E-3m, 0.02198m)

the computer rejected this.

The computer only accepted(0.04678m, 0.0124m)as the correct answer

I was wondering... is the other answer equally as valid or am I missing something?

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# Homework Help: Very simple charge question, please review

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