A weightless thread can bear tension upto 37 N. A stone of mass 500 g is tied to it and revolved in a circular path of radius 4 min a vertical plane. If g = 10 ms-2, then the maximum angular velocity the stone will be
2 rad s-1
4 rad s-1
8 rad s-1
16 rad s-1
B.
4 rad s-1
According to second law, the force f provding the acceleration is
F =
where m is the mass of the body. This force directed towards the centre is called the centripetal force. For a stone rotated in a circle by a string, the centripetal force is provided by the string.
Maximum tension in the thread is given by
Tmax = mg +
⇒ Tmax = mg + mrω2 ( )
ω2 =
Given
Tmax = 37 N, m = 500 g = 0.5 kg,
g = 10 ms-2, r = 4 m
∴
⇒ ω2 = 16
⇒ ω = 4 rad s-1
