physicshelp
posted by Anonymous on .
In the figure below, four particles are fixed along an x axis, separated by distances d = 4.00 cm. The charges are q1 = +2e, q2 = e, q3 = +e, and q4 = +5e, with e = 1.60 × 1019 C. What is the value of the net electrostatic force on (a) particle 1 and (b) particle 2 due to the other particles?
q1 is at the origin and the rest of the particles are to the right a distance d from one another. therefore the order of particles is q1,q2,q3,q4 each with a distance d in between.
Got part a to be 5.596E26 but i don't know how to do b. please help

The only difference in part 2 from part 1 is that you have to consider space and direction of forces. Do this, sketch which way the forces are.
at q2, reverse the sign of F since it is on the left side.
Ftotal2= k/d^2 (q1q2+q3q2+q4q2/2^2 )
That should do it.
If you want to the direction, You need to do the vector form of the equation. 
i ended up with 2.8767E29 but its incorrect...i don't understand what im doing wrong still

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