What is the primary energy conversion process in an internal combustion engine?

The primary energy conversion process in an internal combustion engine primarily involves transforming chemical energy stored in fuel into mechanical energy that powers the vehicle. This is achieved through a series of controlled explosions occurring within the engine's cylinders, which force pistons to move.

While the option chosen suggests a conversion from potential energy to mechanical energy, it does not accurately reflect how energy transformation occurs in internal combustion engines. The key process involves the combustion of fuel, which releases thermal energy as a result of burning, and this thermal energy is then converted into mechanical energy as it drives the pistons and crankshaft.

Chemical energy is inherent in the fuel (such as gasoline or diesel) and is converted during the combustion process, making the second option, which speaks to the transformation from chemical energy to mechanical energy, the most accurate representation of the primary function of an internal combustion engine.