Electric charge and force question

Thread starter MRoach
Start date Feb 13, 2016
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Charge Electric Electric charge Force

AI Thread Summary

The discussion revolves around a homework problem involving electric charges, specifically finding the value of q3 given charges q1 and q2. The user attempts to calculate q3 by adding the vectors of q1 and q2, arriving at 5 μC. However, the textbook answer states that q3 should be 20 μC, indicating that the force on q1 points in the negative x direction. The confusion seems to stem from the vector addition and the direction of forces involved. Clarification on the correct application of the equations and vector analysis is necessary to resolve the discrepancy.

Feb 13, 2016

MRoach

Homework Statement

q1 = 25 μC at (0,1) and q2 = 20 μC find a.) q3 if q1 is in the negative x direction

Homework Equations

E=kq1q2/r^2

The Attempt at a Solution

I keep trying to add vectors to find q3 ie ( -(25 μC) + 20 μC) and get 5 μC the book answer says 20 μC

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Feb 13, 2016

MRoach

the force on q1 points in the -x direction

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