Answer:
The force exerted by the floor on the gymnast decreases.
Step-by-step explanation:
Gymnasts practice on foam floors. This reduces their injury. If a gymnast falls, the collision time increases. Since the change in momentum is constant, the impulse would be constant. For change in momentum to remain constant, the force exerted by the floor would decrease.
Impulse, I = f × t = Δp = constant.
Thus, as the time of the collision increases, the gymnasts have less impact.