Physics: Cardstock vs. Plastic Tubes for Roller Coaster

[BlueCardBird]

Im wonder if its better to make a rollercoaster from cardstock or plastic tubes? In terms of energy conservation.

 

[Simon Bridge]

Depends how they are to be used.
In general - it should make no difference to the energy conservation of the coaster-vehicle itself provided the track so constructed is sufficiently sturdy.
Plastic tubes and cardstock have different materials properties which may be exploited in different ways - so the question is wide open.