Final answer:
Through the conservation of momentum in Physics, the man flies forward at 5.5 m/s after the collision, which is calculated by dividing the initial momentum by the man's mass.
Step-by-step explanation:
According to this principle, if no external forces are acting on a system, the total momentum of the system remains constant. In the scenario where a man is traveling forward on a scooter and hits a rock, the man flying forward after the collision will have momentum equal to the system's initial momentum, since the scooter stops (assuming no external horizontal forces). The initial momentum of the scooter-man system is the mass of the man plus the mass of the scooter multiplied by their velocity, which is (100 kg + 10 kg) × 5 m/s = 550 kg·m/s. When the man flies off the scooter, the momentum must be conserved, so we use the man's mass and solve for his velocity. The man's new velocity (v) is calculated as the initial momentum divided by the man's mass alone: 550 kg·m/s ÷ 100 kg = 5.5 m/s. Thus, the answer is (A) 5.5 m/s.