Hooke's law describes a certain light spring of unstretched length 31.8 cm. when one end is attached to the top of a doorframe and a 7.52 kg object is hung from the other end, the length of the spring is 40.4 cm. (a) find its spring constant. 856.9 incorrect: your answer is incorrect. your response is off by a multiple of ten. kn/m (b) the load and the spring are taken down. two people pull in opposite directions on the ends of the spring, each with a force of 188 n. find the length of the spring in this situation.