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
Question ID - 51283 | SaraNextGen Top Answer
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 |
|||
|
(a) |
2.5 s |
(b) |
2 s |
|
(c) |
5 s |
(d) |
3 s |
1 Answer
127 votes
Answer Key / Explanation : (b) -
I=150;
=20rad/s2
∴ 
=
t
E=
=1200
1.5
(20t)2=1200J
⇒t = 2s
127 votes
Answer Link
127