Mission CG4 Centripetal Force Requirement
An eraser is tied to a string and whirled in a horizontal circle at a constant speed. The type of force which causes the eraser to turn in a circle is the ____.
Circular motion requires an inward force. To travel along the curved path of a circle, there must be a force directed centripetally. Any object or thing could supply the force as long as it is directed toward the center of the circular path.
Forces are not mysterious or ghostly. A force is simply a push or pull exerted upon an object as a result of its interaction with another object. The eraser is moving in a horizontal circle and there must be another object pushing or pulling on it towards the center of the circle. Make an effort to picture the situation and then ask; What physical object is directly interacting with the eraser to push or pull it toward the center of the circle? If necessary, use the Game Plan section.
Often times, success in physics demands that you have the proper approach - a good game plan. When determining which type of forces supplies the centripetal force requirement, proceed through the list of forces and ask: Is this force present on the object? If yes, ask: In which direction does this force act? Answering these question demands that you understand each type of force. If necessary, use the Hot Link to navigate to a web page that describes each force on the list of force types.
