A stone of mass 2 ~kg is tied at one end of a string of length 2 ~m and is whirled in a horizontal circle. If the string can withstand a maximum tension of 64 ~N , then the permissible maximum number of rotations per minute is

Step-by-step solution

Mass of stone, m =2 ~kg Length of the string = radius, r=2 ~m Maximum tension, T_ =64 ~N aligned & T _ = mv _ ^2 r & 64= 2 v _ ^2 2 & v _ =8 ~m / s & v _ = r _ & 8=2 2 f & f = 2 60= 120 aligned Hence, the permissible maximum number of rotations per minute is 120 .