Final answer:
The floor register has the largest terminal velocity in feet per minute.
Step-by-step explanation:
In fluid dynamics, the terminal velocity of an object is the maximum speed it can reach as it falls through a fluid, such as air. The terminal velocity depends on the shape, size, and weight of the object. In this case, the type of register that will have the largest terminal velocity in feet per minute is the floor register. Floor registers are usually larger in size compared to sidewall registers, round ceiling diffusers, and square ceiling registers. Their larger size allows for more air movement, resulting in a higher terminal velocity.
Learn more about Terminal velocity of registers