The helix of Helix includes the lowest point of the roller coaster, at 17.1 m, just before the second launch?

• What is the speed of the train in the lowest point? (Use the length 12.5 m and estimate the time required for the train to pass!)
• After the first launch the train had the speed 21.3 m/s at an elevation 36.7 m.
• How fast would you have expected the tain to move in the lowest point if the sum of potential and kinetic energy had been unchanged?
• How much energy is "lost" (i.e. converted to heat)? Express the loss in terms of elevation (energy divided my mg).
• The train has moved about 480 m after the first launch. How many cm of elevation has the train lost for each meter of track?
• The movie clip was recorded on a cold day. It it had been warmer, the train may only have lost 2 cm for each meter of track. What speed would you expect on a warmer day?