Question

DUPLICATE. WITH ATTACHMENT
Two tiny spheres of mass = 8.70 mg carry charges of equal magnitude, 72.0 nC , but opposite sign. They are tied to the same ceiling hook by light strings of length 0.530 m . When a horizontal uniform electric field E that is directed to the left is turned on, the spheres hang at rest with the angle between the strings equal to 50 in the following figure. (note that q1 is positive and it is the left once)
What is the magnitude E of the field?

Answer 1

Even though im ot giving you the whole answer I can tell you what to do and why to do it. If what you need is to find the Electric field of something you need to use the formula for that wich is E = kQ/r2 where k is a constant with a value of 8.99 x 109 N m2/C2., Q is a charge of magnitude and you have also the ratio. So replace the simbols with the data they give you. I know thi will help you