Final answer:
The correct answer to the parking question is 'false;' you should turn wheels toward the curb. The concept of potential energy conversion to kinetic and some energy dissipating as heat explains why a cyclist doesn't reach the same height on the opposite hill and why a truck warms up as it rolls down a hill.
Step-by-step explanation:
The statement 'When parking your vehicle on a downhill section of roadway, you should always turn your wheels away from the curb' is false. When parking on a downhill grade, you should turn your wheels toward the curb or right shoulder. This way, if your vehicle starts to move, it will roll into the curb instead of into traffic. The principle behind this is to ensure safety and prevent the vehicle from becoming a hazard to other road users.
As for the physics concepts involved in the question's given scenarios, when a cyclist coasts down a hill and then up another, some of the original potential energy is indeed converted into heat due to friction. Heat causes the bicycle tires to warm up, and as a result, not all of the potential energy is converted into kinetic energy to reach the same height on the opposite hill, resulting in a lower stopping point.
Similarly, a truck that is parked at the top of a hill and allowed to run freely to the bottom will convert its potential energy at the top to kinetic energy as it descends. Just like the cyclist, some of this energy would also be dissipated as heat due to friction.