At each corner of an equilateral triangle, there is a charge, as diagrammed below. The length of each side of the triangle is .4 meters. Find the net force acting upon q1, given the following values for each of the charges: q1 = −2.00 μC, q2 = 3.00 μC, and q3 = 4.00 μC.

Question

At each corner of an equilateral triangle, there is a charge, as diagrammed below.  The length of each side of the triangle is .4 meters.  Find the net force acting upon q1,  given the following values for each of the charges:  q1 = −2.00 μC, q2 = 3.00 μC, and q3 = 4.00 μC.

Damon · Answer

forces on q1 attractive
k =10^-12* usual k to account for μ
force in direction of Fq3=k(8)/.4^2
force in direction of Fq2=k(6)/.4^2
force perpendicular to opposite side
Fy= Fq3 cos 30 + Fq2 cos 30

force parallel to opposite side
Fx= Fq3 cos 60 - Fq2 cos 60

F = sqrt(Fx^2+Fy^2) as usual