When person whirled a stone which is tied to a string around against in a circle. If you cut the string then the stone flies off tangentially due to inertia of

When a person whirled a stone which is tied to a string around against in a circle. If you cut the string then the stone flies off tangentially due to the inertia of the direction 

The centripetal force stops acting when the string breaks. Due to inertia, the stone continues to move along the tangent to a circular path. So, the stone flies off tangentially to the circular path