Q. Collar A can slide on a frictionless vertical rod and is attached to a spring. The constant of the spring is 0.5 N/mm, and the spring is unstretched when h=90 mm. Knowing that the system is in equilibrium when h = 120 mm, determine the weight of the collar.

a) The velocity and acceleration vector of the car at point B (using normal and tangential coordinates).

b) The velocity and acceleration vector of the car at point B (using Cartesian xy coordinates).

c) The time t that the car passes from point B and point C (assume time at point , ). At s=0