Question

A stone of mass 0.3 kg is tied to the end of a string. It is whirled in a circle of radius 1m with a speed of 40 rev min⁻¹ . If the string can withstand a maximum tension of 200 N, then find the tension and maximum speed with which the stone can be whirled.  

Answer 1

Now, for maximum velocity, tension is maximum. From formula (ii), 

For the stone whirled in a circle

i. the tension in the string is 5.258 N. 

ii. the maximum speed is 25.82 m/s.