Two tiny spheres of mass 7.80 mg carry charges of equal magnitude, 82.0 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 θ between the strings equal to 58.0∘ (Figure 1). What is the magnitude E of the field?

Two tiny spheres of mass 7.80 mg carry charges of equal magnitude, 82.0 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 θ between the strings equal to 58.0∘ (Figure 1). What is the magnitude E of the field?