Q107
General SciencePhysics
A stone tied to a string is whirled in a circle. As it was revolving, the rope suddenly snaps. Then
- a.the stone flies off tangentially
- b.the stone moves radially outwards
- c.the stone moves radially inwards
- d.None of the above
Answer: (A) the stone flies off tangentially
A stone whirled in a circle is kept on its path by the tension of the string, which supplies the centripetal force towards the centre. When the string snaps this force vanishes, and by Newton's first law (inertia of direction) the stone moves in a straight line along the tangent at that point. It does not fly radially outward; the 'centrifugal force' is only a pseudo-force felt in the rotating frame.