Final answer:
The acceleration experienced by riders during free fall on the power tower is 1g, which is the standard acceleration due to gravity.
Step-by-step explanation:
During the portion of the ride where riders are launched skyward with an acceleration of 4g, they are experiencing an acceleration four times that of Earth's gravitational pull. When they experience a period of free fall, the only acceleration acting on them is the acceleration due to gravity, which is 1g, or 9.8 m/s².
Therefore, during free fall, the riders do not experience the initial 4g acceleration but instead experience the standard acceleration of gravity, which is 1g.
The acceleration experienced by the riders on the power tower is 4g.
When the riders are launched skyward, they experience an acceleration of 4g. This means that their acceleration is four times the acceleration due to gravity, which on Earth is approximately 9.81 m/s². So, the acceleration experienced by the riders is 4 times 9.81 m/s², which equals 39.24 m/s².
Therefore, the correct answer is 4) 5g.