A person of mass 70kg is standing on a weighing scale inside an elevator. The elevator starts from rest at the ground floor and moves according to the schedule given below:
• Phase I: Accelerates upward uniformly at 2m s−2 for 4s.
• Phase II: Continues upward at constant speed for 6s.
• Phase III: Decelerates uniformly at 3m s−2 until it comes to rest at the top floor.
a. (i) For each phase, draw the free-body diagram of the person.
b. (ii) Calculate the reading of the weighing scale during each phase.
c. (iii) Identify the maximum and minimum readings recorded by the scale throughout the journey.