Physics Problem: Minimum Height to Loop the Loop

[@fizixx]

I like the couple extras you added to this problem.

[@asterixx6878]

If the car rolls down the track, the wheels will have kinetic energy due to rotation. The energy is of course taken from the energy the car had at the beginning (mgh). So - the calculated height will not be enough to make a full loop, with the consequence that a terrible accident will happen.😃
If the car slides without friction, then the calculation is ok.