Answer:
20.26 Nm
Step-by-step explanation:
r = 1.23 m , m = 93.6 kg, w = 0, f0 = 369 rpm = 369 / 60 = 6.15 rps
w0 = 2 x 3.14 x 6.15 = 38.622 rad/s
t = 2.25 min = 2.25 x 60 = 135 second
Moment of inertia = 1/2 m r^2 = 0.5 x 93.6 x 1.23 x 1.23 = 70.8 kg m^2
use first equation of motion for rotational motion
w = w0 + α t
0 = 38.622 - α x 135
α = 0.286 rad/s^2
torque = moment of inertia x angular acceleration
Torque = 70.8 x 0.286 = 20.26 Nm