A stone of mass 0.25 kg tied to the end of a string is whirled round in a circle of radius 1.5 m with a speed of 40 rev./min in a horizontal plane. What is the tension inthe string ?What is the maximum speed with which the stone can be whirled around if the string can withstand a maximum tension of 200 N ?

A stone of mass 0.25 kg tied to the end of a string is whirled round i

1.	A stone of mass 0.25 kg tied to the end of a string is whirled round in a circle of radius 1.5 m with a speed of 40 rev./min in a horizontal plane. What is the tension inthe string ?What is the maximum speed with which the stone can be whirled around if the string can withstand a maximum tension of 200 N ?
Answer» Solution :`V = 2pi xx 1.5 xx 40/60 = 2pi MS^(-1)` `T = (mv^2)/(R ) = (0.25 xx 4pi^2)/(1.5) = 6.6 N` `200 = (mv_(MAX)^2)/(R ) ` . Which gives`v_(max) = 35 ms^(-1)`