
Answer:
1.31×10⁻⁴ C or 131 μC
Explanation:
From the question,
Applying Coulomb's Law,
F = kqq'/r²..................... Equation 1
Where F = Force between the charges, q = first charge, q' = second charge, r = distance between the charges, k = coulomb's constant.
make q' the subject of the equation
q' = F×r²/(kq)
q' = Fr²/kq................ Equation 2
Given: F = 1240 N, r = 16.4 cm = 0.164 m, q = 28.4 μC = 2.84×10⁻⁵ C,
Constant: k = 8.98×10⁹ Nm/C²
Substitute these values into equation 2
q' = (1240×0.164²)/[(2.84×10⁻⁵)×(8.98×10⁹)
q' = (33.35104)/(25.5032×10⁴)
q' = 1.31×10⁻⁴ C
q' = 131 μC