For me it is the fact that our blood contains iron. I earlier used to believe the word stood for some ‘organic element’ since I couldn’t accept we had metal flowing through our supposed carbon-based bodies, till I realized that is where the taste and smell of blood comes from.
the inertia from the cars current speed is used to spin the engine rather than the engine spinning the wheels, the resistances of the engine is what causes the slowing effect
modern cars with fuel injection can complete disable injecting fuel when not needed and can also adjust the timing of the injections for maximum efficiency