A large grinding wheel in the shape of a solid cylinder of radius 0.330 m...

The information below pertains to solid cylinder wheels rotating on a vertical axis without any friction.
${\displaystyle \alpha =0.94\frac{rad}{s^2}}$ 
${\displaystyle F=250N}$ 
${\displaystyle r=0.33m}$ 
Torque is given by: 
${\displaystyle \tau =F\cdot r=I\cdot \alpha }$ 
Addressing the issue of moment of inertia
${\displaystyle I=\frac{F\cdot r}{\alpha }=\frac{250\cdot 0.33}{0.94}=87.8}$ 
Inertia moment is determined by:
${\displaystyle I=\frac{1}{2}\cdot m\cdot r^2}$ 
Solving it for mass: 
${\displaystyle m=\frac{2\cdot I}{r^2}=\frac{2\cdot 87.8}{{0.33}^2}=1612.5}$ kg