A spring has a length of 0.250 m when a 0.27-kg mass hangs from it, and a length of 0.920 m when a 2.3-kg mass hangs from it. a. What is the force constant of the spring? k = N/m b. What is the unloaded length of the spring? = cm a. A novelty clock has a 0.0100-kg-mass object bouncing on a spring that has a force constant of 1.35 N/m. What is the maximum velocity of the object if the object bounces 3.00 cm above and below its equilibrium position? Umax = m/s b. How many joules of kinetic energy does the object have at its maximum velocity? x 10-4 J KEmax =