Which description best fits dynamic torque in escalator operation?

Dynamic torque in escalator operation refers to the force required to maintain a constant or steady speed once the escalator is operational. It accounts for the continuous energy needed to overcome factors such as friction and the weight of the escalator itself, ensuring it runs smoothly without accelerating or decelerating abruptly.

While other forces are indeed important in different contexts (such as startup torque, which is essential for getting the escalator moving initially, or safety-related forces that might prevent accidents), these do not characterize the ongoing operational adjustments necessary to keep the escalator at a steady pace. Hence, the concept of dynamic torque is clearly aligned with maintaining this consistent speed during operation.