Which of the following affects the efficiency of power transmission in a propulsion system?

The alignment of gears and shafts is crucial for the efficiency of power transmission in a propulsion system. Proper alignment ensures that the components fit together smoothly, minimizing friction and energy loss during operation. When gears and shafts are misaligned, it can lead to increased friction and wear, which not only affects the performance of the system but can also lead to premature failure of components. Efficient power transmission is key to optimizing the performance of a propulsion system, and alignment plays a significant role in achieving that efficiency.

Other factors, such as the size of the engine, can influence overall power output but do not directly impact the transmission efficiency as alignment does. The type of fuel used affects engine performance and emissions but is less relevant in the context of power transmission efficiency itself. Weather conditions can impact performance for various reasons, such as how engines operate in different temperatures, but they do not affect the mechanical interactions of gears and shafts that are central to power transmission efficiency.