Circular and Satellite Motion - Mission CG1 Detailed Help

An object is moving in a circle. The velocity of the object at any given moment is directed ____.


Velocity Vector:
A vector is a quantity that is fully described by both a magnitude and a direction. Velocity is a vector that has a magnitude and direction. The magnitude (or value) of the velocity is the object's speed. The direction of the velocity vector is the direction that the object is moving.

Picture a circle (or better off, draw one) and picture an object moving along the path traced out by the circle. Suppose that it's a car with a big humongous arrow pointing straight out its front. (Try not to laugh.) The direction that the arrow points is the direction that the car is moving. (See Know the Law section.) At all points along the circle, the arrow is pointing in a direction that would intersect the circle at a single point. Such a direction is described as being tangent to the circle. As the car makes the big turn around the circle, the direction may change from north, to northeast, to east, to southeast, to south, etc. However, these directions can all be described as being tangent to the circle at the point on the circle where the car is located at that specific instant in time.