Answer:
3.8 m
No mass does not matter
Explanation:
It is given that the tube is frictionless which means there will be no loss of energy. To solve this question we can use the law of conservation of energy which states that energy cannot be created not destroyed but it can be converted from one form to another but energy remains conserved. The form of energies that exist in this system are Kinetic energy (KE) and potential energy (PE).
KE = ½ mv²
PE = mgh
another equation required in this question is equation of motion
s = ut + 1/2at²