Answer:
474.34 m
Step-by-step explanation:
From the question,
E = kq/r²................. Equation 1
Where E = Electric Field, k = coulomb's constant, q = Charge, r = distance.
Make r the subject of the equation
r = √(kq/E)............ Equation 2
Given: q = 50 nC = 50×10⁻⁹ C, E = 0.002 N/C
Constant: k = 9×10⁹ Nm²/C².
Substitute these values into equation 2
r = √(50×10⁻⁹×9×10⁹/0.002)
r = √(450/0.002)
r = √(225000)
r = 474.34 m