Two charged non-conducting spheres, each with charge 1 $\mu\text{C}$, are placed at the end of a non-conducting spring of natural length 0.1 m and spring constant 1000 N/m. What is the distance the spring is stretched when it comes to rest in m?
• The electrostatic constant is $9 \times 10^9~\text{Nm}^2/\text{C}^2$.