Understanding the Motion of a Pendulum

Oct 13, 2025 by wbrum.org 79 views

**What If a String Tied to a Stone Swinging in a Horizontal Circle Line Breaks?** ===========================================================

Introduction

When a string tied to a stone is swinging in a horizontal circle, it is an example of a simple pendulum. The motion of the pendulum is governed by the laws of physics, specifically the conservation of energy and the concept of centripetal force. In this article, we will explore what happens if the string tied to the stone breaks while it is swinging in a horizontal circle.

Understanding the Motion of a Pendulum

A pendulum is a weight suspended from a pivot, and it swings back and forth in a circular motion. The motion of a pendulum is governed by the following factors:

Gravity: The force of gravity pulls the pendulum downwards, causing it to swing in a circular motion.
Centripetal force: The force that keeps the pendulum moving in a circular path is called centripetal force. This force is directed towards the center of the circle.
Conservation of energy: The total energy of the pendulum remains constant, but it is converted from potential energy to kinetic energy and back again as the pendulum swings.

What Happens When the String Breaks

When the string tied to the stone breaks, the centripetal force that was keeping the stone in a circular motion is suddenly removed. As a result, the stone will no longer be constrained to move in a circular path, and it will fly off in a straight line.

Q&A

Q: What is the direction of the stone after the string breaks?

A: The direction of the stone after the string breaks is in a straight line, tangent to the circle at the point where the string broke.

Q: What is the speed of the stone after the string breaks?

A: The speed of the stone after the string breaks is the same as its speed at the point where the string broke. This is because the force of gravity is still acting on the stone, and it is not affected by the breaking of the string.

Q: What is the trajectory of the stone after the string breaks?

A: The trajectory of the stone after the string breaks is a straight line, with a constant speed and direction. The stone will continue to move in this direction until it is affected by external forces, such as air resistance or friction.

Q: Can the stone be caught or stopped after the string breaks?

A: Yes, the stone can be caught or stopped after the string breaks. However, this would require a significant amount of force or energy to be applied to the stone, as it is now moving in a straight line with a constant speed.

Q: What is the relationship between the breaking of the string and the conservation of energy?

A: The breaking of the string does not affect the conservation of energy. The total energy of the pendulum remains constant, but it is now converted from potential energy to kinetic energy, and the stone is moving in a straight line with a constant speed.

Q: Can the stone be made to swing in a circular motion again after the string breaks?

A: No, the stone cannot be made to swing in a circular motion again after the string breaks. The breaking of the string removes the centripetal force that was keeping the stone in a circular motion, and it is now free to move in a straight line.

Conclusion

In conclusion, when a string tied to a stone swinging in a horizontal circle line breaks, the stone will no longer be constrained to move in a circular path, and it will fly off in a straight line. The direction, speed, and trajectory of the stone after the string breaks are determined by the laws of physics, specifically the conservation of energy and the concept of centripetal force.

References

University of Colorado Boulder. (n.d.). Simple Pendulum. Retrieved from https://www.colorado.edu/physics/2000/pendulum/pendulum.html
Physics Classroom. (n.d.). Pendulum Motion. Retrieved from https://www.physicsclassroom.com/class/motion/Lesson-1/Pendulum-Motion
Wikipedia. (n.d.). Pendulum. Retrieved from https://en.wikipedia.org/wiki/Pendulum