Rollercoaster Simulation

[jczerts]

I've been trying to build roller coaster loops to use for my physics (circular motion) investigation.
How do you create curved tracks using the Polygon tool, and how is the actual cart connected onto the rails?
Is there a way to measure the dimensions (like height) of my loops/tracks?
I've gone through every tutorial, yet these things are still unclear to me.
As a new user, I'd appreciate some help

[Kilinich]

Curves ara made from circles using "combine shapes".
How to connect is up to you.
Dimensions could be measured with box (turn on ruler on it)

[jczerts]

Thank you so much!
Just one more thing, I made two separate tracks on different files and merged them into one file.
When I run the simulation, the cart runs off the second track.
How could I fix this?