A wheel comprises a ring of radius R and mass M and three spokes of mass m each. The moment of inertia of the wheel about its axis is

Options

A. `(M+(m)/(4))R^(2)`
B. `(M+m)R^(2)`
C. `(M+3m)R^(2)`
D. `((M+m)/(2))R^(2)`

Answer

B

Explanation

The moment of inertia,
`I=I_("ring")+3I_("spoke")=MR^(2)+3((Ml^(2))/(3))=(M+m)R^(2)`