When no external torque acts on a system, the law of conservation of angular momentum comes into effect. Angular momentum is a fundamental property in physics that remains constant in a closed system without external influences. In the case of a ball moving along an orbit in space, its angular momentum is conserved as long as there is no external torque acting on it.

The angular momentum of the ball depends on its mass, velocity, and the distance from the center of rotation. Since no external torque is being applied, these parameters remain unchanged, ensuring the angular momentum is conserved. As a result, the ball will continue to move along its original orbit with the same angular velocity. The absence of external forces ensures that its motion remains stable and unaffected.

This principle is significant in explaining the behavior of celestial bodies, such as planets orbiting the Sun or satellites around Earth. It also applies to artificial objects in space, ensuring their predictable motion in the absence of external influences. The conservation of angular momentum highlights the importance of external torques in altering rotational motion, making it a cornerstone in the study of dynamics and orbital mechanics.