Along a straight line tangential to the circular path.
Explanation
The phenomenon is governed by Newton's First Law of Motion, specifically the concept of inertia of direction. Uniform circular motion requires a continuous force directed towards the center, known as centripetal force, to constantly change the direction of the object's velocity.
Analysis
- Role of Tension: When the stone is whirled, the tension in the string provides the necessary centripetal force. This force acts perpendicular to the velocity of the stone, altering its direction but not its speed.
- Direction of Velocity: At any given instant in a circular path, the velocity vector of the object is directed along the tangent to the circle at that point.
- Effect of Breaking the String: When the string breaks, the centripetal force (tension) instantly becomes zero. According to Newton's First Law, an object will continue in its state of motion along a straight line unless acted upon by an external force.
- Resultant Path: Since the constraining force is removed, the stone retains its instantaneous velocity direction. Therefore, it flies off in a straight line tangential to the circular path at the point of release.
Key Takeaway: In the absence of centripetal force, an object previously in circular motion follows a straight-line path tangential to the circle due to the inertia of direction.