A wheel of radius `0.4m` can rotate freely about its axis as shown in the figure. A string is wrapped over its rim and a mass of `4 kg` is hung. An angular acceleration of `8 rad//s^(2)` is produced in it due to the torque. Then, the moment of inertia of the wheel is (`g=10m//s^(2)`)

Options

A. `2 kg-m^(2)`
B. `1.36 kg-m^(2)`
C. `4 kg-m^(2)`
D. `8 kg-m^(2)`

Explanation

`tau=I_(0)alpha`
`40xx0.4=[I+4xx(0.4)^(2)](8)`
`I+0.64=2`
`I==1.36 kg m^(2)`