An empty box of mass 5kg is found to accelerate up at the rate of `g/6` when a constant force `vec(F)` is applied on it. Howm much mass (in kg ) of sand be filled in it so that box may accelerate down at the same rate ? (g beight the acceleration due to gravity).

Answer

5

Explanation

`I=(ml^(2))/3xx3=ml^(2)=10xx(1.25)^(2) =250/16`
`omega=omega_(0)+alphar`
`(1900-1400)xx(2pi)/60=(25pi)/250 xx16 t`
`t=240/48 = 5 sec.`