Final answer:
An object constrained by a cord to move is influenced by forces like tension, weight, and possibly normal force and friction. Tension within a cord is equal throughout and centripetal force is applied when objects are attached to a pivot. Physics simulations can help visualize the effects of tension.
Step-by-step explanation:
An object constrained by a cord to move is subject to various forces, which include the weight of the object, tension in the cord, normal force, and friction when relevant. The weight is the gravitational force acting vertically downward. The cord exerts a tension force that is equal and opposite at any point along its length, thanks to Newton's third law. If an object is attached by a cord to a pivot point on a frictionless surface, such as in centripetal force scenarios, a force applied perpendicular to the radius causes the object to accelerate about the pivot, keeping the force perpendicular to the radius at all times. In hands-on simulations such as Virtual Physics, you can explore how changing the number of people pulling on a tug-of-war rope affects the net force and outcome, representative of tension forces in action.