A block is on a surface with μₛ=0.325. It takes 4.11 N to
break it free from static friction.
How much normal force acts
on the block?
(Unit = N)

Aspring is used to stop a 50-kg package which is moving down a 20º incline. the spring has a constant k = 30 kn/m and is held by cables so that it is initially compressed 50 mm. knowing that the velocity of the package is 2 m/s when it is 8 m from the spring and neglecting friction, determine the maximum additional deformation of the spring in bringing the package to rest.