Moment of inertia of a body about a given axis is 1.5 kg . Initially the body is at rest. In order to produce a rotational kinetic energy of 1200 J, the angular acceleration of 20 rad/ must be applied about the axis for a duration of |
|||

(a) |
2.5 s |
(b) |
2 s |

(c) |
5 s |
(d) |
3 s |

Moment of inertia of a body about a given axis is 1.5 kg . Initially the body is at rest. In order to produce a rotational kinetic energy of 1200 J, the angular acceleration of 20 rad/ must be applied about the axis for a duration of |
|||

(a) |
2.5 s |
(b) |
2 s |

(c) |
5 s |
(d) |
3 s |

1 Answer - 5876 Votes

3537

I=150;

=20rad/s^{2}

∴ = t

E= =1200

^{ } 1.5 (20t)^{2}=1200J

⇒t = 2s