I observe two phenomena:
Obs-1: I don't have the materials here to perform this experiment.
Obs-2: You have not done the assigned experiment, and you apparently have no intention of doing it.
Energy can be one answer! There are many, but energy is a main one.
Answer:
3 m/s^2
Explanation:
acceleration= Change in velocity/time
= 30-0 / 10
= 30/10
=3 m/s^2
Answer:
20.62361 rad/s
489.81804 J
Explanation:
= Initial moment of inertia = 9.3 kgm²
= Final moment of inertia = 5.1 kgm²
= Initial angular speed = 1.8 rev/s
= Final angular speed
As the angular momentum of the system is conserved

The resulting angular speed of the platform is 20.62361 rad/s
Change in kinetic energy is given by

The change in kinetic energy of the system is 489.81804 J
As the work was done to move the weight in there was an increase in kinetic energy