When the end of the spring is moved to a different location \(x\), the response force from the spring is linear in the displacement \(\x-x_0|\), with a constant of proportionality \(k\) (the spring co...When the end of the spring is moved to a different location \(x\), the response force from the spring is linear in the displacement \(\x-x_0|\), with a constant of proportionality \(k\) (the spring constant). Since the direction of the force is opposite of the displacement (compressed springs push against the compression, whereas stretched springs pull back - this is why the spring force is often called a restoring force), we need to be a little careful to get that right.
