Question

two charge of magnitude 3.6 mc and -3.6 mc are placed at the corners a and b of an equilateral triangle abc of side 6cm. find the force experienced by the charge 2mc placed at c.​

Answer 1

Let F1 and F2 exerted by the charge placed at A and B point of the equilateral triangle on C point as shown in the figure 

F1=r2KqAqc=(.3)29×109×3×10−9×2×10−9=6×10−7

F2=r2KqBqc=(.3)29×109×(−3)×10−9×2×10−9=−6×10−7

both F1 and F2 make angle of 120^0 between each other

resultant of F1 and F2 is F

⇒F2=F12+F22+F