A wheel having moment of inertia `2 kg m^(2)` about its vertical axis, rotates at the rate of `60 rpm` about this axis. The torque which can stop the wheel's rotation in one minute would be

Options

A. `(pi)/(18)Nm`
B. `(2pi)/(15)Nm`
C. `(pi)/(12)Nm`
D. `(pi)/(15)Nm`

Answer

D

Explanation

`tauxxDeltat=L_(0)" "{because" since"L_(f)=0}`
`implies tauxxDeltat=Iomega`
or `tauxx60=2xx2xx60pi//60{becausef=60"rpm" tau=(pi)/(15)N-m therefore omega=2pif=2pixx(60)/(60))`