1. The problem statement, all variables and given/known data A spring has an equilibrium length of 20.0 cm and a spring constant of 51.9 N/m. The spring is connected to the underside of the roof of a car and a 0.214 kg block suspended from it. How long (in cm) is the spring when the car is at rest? How long is the spring if the car is accelerating horizontally at 1.63 m/s2? 2. Relevant equations mgh=0.5kh^2 mg=0.5kh 3. The attempt at a solution Nothing is working for me and I don't know what I'm missing!