I am rather confused about springs. This may be an obvious question, so just bear with me. Now, say you had two spheres of any mass, a spring (that obeys Hooke's Law) connecting them, and the whole system was without external forces or friction (we can say, suspended in space). Now, what would happen if you applied a force to one of the spheres, in the direction of the other sphere? How far would the spring contract - would it even contract in the first place?