What percentage of stream energy is primarily used to overcome friction?

The correct answer indicates that a significant portion of stream energy is dedicated to overcoming friction. In river and stream dynamics, a large amount of energy generated by the flow of water is absorbed in overcoming resistance caused by friction between the water and the channel bed and banks. This frictional force impacts the flow's velocity and energy efficiency, meaning that streams must utilize a major portion of their potential energy to maintain motion against this resistance.

The acknowledgment that friction plays a critical role in energy consumption is supported by fluid dynamics principles, which illustrate that as water flows over varying terrains, the energy loss due to friction can be quite substantial. Therefore, when considering the total energy available in a stream, a high percentage, such as 95%, accurately reflects the considerable energy that is expended in overcoming this frictional force, which is critical to understanding stream mechanics and hydrology.