Answer:
a) 7.5425 * 10^-7 C
b) 3.7712 * 10^-7 C ; 1.5085 * 10^-6 C
Explanation:
Part a)
[tex]F_{elect} = \frac{k*q_{1}*q_{2} }{R^2} \\q_{1} = q_{2} = q\\q = \sqrt{\frac{F_{elect} * R^2}{k} }\\ = \sqrt{\frac{0.2 * 0.16^2}{9*10^9} }\\\\ q = 7.5425 * 10 ^(-7) C[/tex]
Part b)
[tex]F_{elect} = \frac{k*q_{1}*q_{2} }{R^2} \\q_{1} = 4*q_{2} \\q = \sqrt{\frac{F_{elect} * R^2}{k*4} }\\ = \sqrt{\frac{0.2 * 0.16^2}{4*9*10^9} }\\\\ q_{2} = 3.7712 * 10 ^(-7) C\\\\q_{1} = 1.5085 * 10 ^(-6) C[/tex]