1. The problem statement, all variables and given/known data Consider two small balls with charges +q and -q, connected by a spring with spring constant k. A homogeneous electric field E has been turned on. E is collinear with the line that connects -q to +q. By how much will the string stretch? 2. Relevant equations Coulomb's Law Hooke's Law 3. The attempt at a solution I figured that we could use F=-kx and substitute Coulomb's Law in for F. Doing this and solving for x, I obtained (1/(-4πεk))(q^2/r^2), where ε is the permittivity constant and k is the spring constant. Was this the correct way to approach this problem? Any input would be appreciated. Thanks!