Point charges in an electromagnetic field

[nmendoza37]

point charges in an electric field

Homework Statement

Problem: A +8.75 micro C point charge is glued to a frictionless table. It is tied to -6.5 micro C point charge by a 2.5 cm string (weightless and nonconducting). A uniform electric field of magnitude 1.85*10^8 N/C is directed parallel to the wire toward the positive charge. a) what is the tension in the wire? b) what would the tension be if both charges were negative?

Homework Equations

F=k(q1)(q2)/r^2

E(vector)= F(vector)/(q)

The Attempt at a Solution

using coloumbs law I attempted to find the force between the 2 particles. but from there i am pretty lost can anyone help?

 

[nmendoza37]

Work

q1= 8.75*10^-6 C
q2=-6.5*10^-6 C
r=.025 m

so Force=(8.988*10^9) X (q1*q2)/r^2 = 8.1*10^-4 N (q1*q2) is absolute value

but where do i go from here?