Answer:
formula used K=F/∆l
∆l is the elongation of the spring
- F=10N
- ∆l=20mm===> 0.02m
- K=10N divided 0.02m= 500N/m
if we are walking on a perfectly smooth ground which has no friction our force would simply cancel out the force reverted by the ground and we would fall.
We need it to help push out feet off the ground
Hope those helps :)
