What effect does an increase in speed have on profile drag?

An increase in speed directly affects profile drag by causing it to increase. Profile drag, also known as form drag, arises from the shape of an object and its interaction with the fluid (in this case, air) as it moves through it. As the speed of the object increases, the air flow around it becomes more turbulent, leading to a rise in drag forces acting against the object due to the increased pressure differentials and friction between the object's surface and moving air.

When an object like an aircraft is moving faster, it encounters more air molecules in a given time frame, which leads to greater resistance. This increase in drag is typically not linear; it usually grows with the square of the speed, meaning that even a small increase in velocity can result in a substantial rise in profile drag. Understanding this relationship is crucial for the design and performance optimization of aircraft, vehicles, and other objects traveling through air or fluid mediums.