Final answer:
Appropriate streamlining leads to a decrease in the drag coefficient, which reduces aerodynamic drag on an object moving through a fluid.
Step-by-step explanation:
By appropriate streamlining, the drag coefficient decreases. Reducing the drag coefficient is a principal goal in aerodynamic design for objects moving through fluid, such as air. Streamlining is the process of shaping an object to allow the fluid to move past it more smoothly, which minimizes resistance and, consequently, reduces the drag. When an object is streamlined, the drag force acting on it diminishes due to a lower drag coefficient, which implies that the object will experience less aerodynamic drag as it moves through the fluid. This is particularly important for high-speed vehicles like cars, airplanes, and boats where performance and fuel efficiency are essential.
In relation to the other questions, the coefficient of kinetic friction typically remains constant and independent of relative motion. As for a body going through a loop, factors like kinetic energy at different positions in the loop can vary. Bernoulli's equation implies that if the pressure is constant and kinetic energy per unit volume increases, the potential energy per unit volume of the fluid decreases. Lastly, if a fluid's velocity changes, the drag related to that fluid also changes depending on other factors such as cross-sectional area and fluid density.