File:Uniform circular motion.PNG
File:Uniform circular motion.PNG
Uniform Circular Motion (UCM)
















A funny (or at least) mildly entertaining rap about Uniform Circular Motion!

Basics of Uniform Circular Motion:

- it is the motion of an object moving in a circle, at a constant speed
- although the object moves at a constant speed its velocity is not constant
- this is because velocity is a vector and depends on not only the speed of the object but the direction as well
- when an object is moving in a circle, it constantly changes its direction
- although the direction changes, the distance from the object to the axis of rotation remains constant (the length of the radius)
- an object moving in a circle is accelerating because of the changing velocity
- the direction of acceleration is inwards
- the net force acting on an object moving in uniform circular motion is directed to the center of the circle
- the force is called an inward or centripetal force
- the centripial force is also known as the "center seeking force"
- it can be the force of tension, gravity, or friction
- without this force, the object would travel in a straight line
- the force is perpendicular to the velocity vector
- to calculate the quantitiy of this force use:
centripial force = m(v^2)/radius

Anim'n of object undergoing UCM
Anim'n of object undergoing UCM









This illustration shows the path that an object in UCM takes. Notice the velocity, v, is constantly changing direction, and acceleration, a, remains constant. Imagine there is another variable there,f, representing the centripial force. This force would be in the same position as accleration, due to the fact that the force is perpendicular to the velocity vector in order to keep the object moving in a circle.