A small fly-wheel is subjected to an unknown external torque about its central axis. Measurements of its angular momentum L at discrete times are recorded in the table below.
t (s)
0
1
2
3.5
5
L (kg·m²/s)
2
5
8
8
1
Treat L as varying linearly between consecutive data points.
(a) Calculate the average net external torque acting on the fly-wheel between t = 0 s and t = 2 s.
(b) Determine the average net external torque between t = 2 s and t = 3.5 s.
(c) Determine the average net external torque between t = 3.5 s and t = 5 s.
(d) Based on your results, discuss whether the direction of the net external torque changed over the 5-s interval, citing numerical evidence from your calculations.