A weightless thread can bear tension upto 3.2 kg weight. A stone of mass 500 g is tied to it and removed in a circular path of radius 4 m is vertical plane. If `g=10^(2)m//s^(2)`, the maximum agular velocity of the stone is

Options

A. 2 rad/s
B. `sqrt(21)` rad/s
C. 16 rad/s
D. 4 rad/s

Answer

D

Explanation

For motion under vertical plane
`T_("max")=(mv_("max")^(2))/(r )+mg`
`rArr T_("max")=mv omega_("max")^(2)+mg,`
`omega^(2)=(T_("max")-mg)/(mr)`
`=(37xx10-500xx10^(-3)xx10)/(500xx10^(-3)xx4)`
`omega=sqrt(16)=4` rad/s