Final Answer:
Both will move at the same speed through the roller coaster - a dozen middle school children or a dozen grown men
Theref, correct option is 3) Both will move at the same speed.
Step-by-step explanation:
The speed at which objects move through a roller coaster is primarily determined by the force of gravity acting on them, which is independent of their individual masses. In this case, both a dozen middle school children and a dozen grown men will experience the same gravitational force, leading to the conclusion that they will move at the same speed through the roller coaster.
Gravity is a universal force that affects all objects equally, regardless of their mass. When the roller coaster descends, it converts the potential energy gained at the top of the track into kinetic energy, causing the cars and their occupants to accelerate.
Since gravity acts uniformly on all objects, the acceleration experienced by both groups—middle school children and grown men—will be identical, resulting in the same speed for both.
Theref, correct option is 3) Both will move at the same speed.