Answer:
k = 5178.8 N/m
Explanation:
As we know that spring mass system will oscillate at angular frequency given as
now we have
now the maximum acceleration of the spring block system is at its maximum compression state which is given as
here A= maximum compression of the spring
so here in order to find maximum compression of the spring we will use energy conservation as we know that initial total kinetic energy of the car will convert into spring potential energy
here we know that
v = 85 km/h
now we have
now from above equation of acceleration we have