Answer:
b) 0.5 N
Explanation:
From coulomb's law,
F = kq'q/r².................... Equation 1
Where F =force of repulsion between the charges, q' = first charge, q = second charge, r = distance between the charges, k = proportionality constant.
q'q = Fr²/k........................... Equation 2
Given: F = 2 N, r = 1 m, k = 9.0×10⁹ Nm²/C²
Substituting into equation 2
q'q = 2(1)²/(9.0×10⁹)
q'q = 2/9.0×10⁹ C².
If the distance between the charges is increased to 2 meters,
r = 2 m, q'q = 2/9.0×10⁹ C².
Substitute into equation 1
F = 9.0×10⁹(2/9.0×10⁹)/2²
F = 2/4
F = 1/2 = 0.5 N.
The right option is b) 0.5 N
