uniform circular motion terms

For the topic uniform circular motion, you will need to know these terms/facts:

angular velocity: How fast something travels around a circle; typically given in radians per second = rad/s = w

linear velocity: Can be used to describe the speed of something moving along a circular path. Typically given in m/s. Best way to think of it: if you swing a rock on a string and let go, the velocity of the flying rock is the linear velocity.

centripetal force: The force that keeps an object moving in a circle. It acts toward the center of rotation. This force is why you lean in your seat when your car is making any type of a turn.

centrifugal force: A mysterious force that exists differently from how most people think of it.. If it did, when you released a rock twirling on a string, the rock would fly outward... this does not happen. The rock flies straight in the direction it was moving when you released it ==> INERTIA! The centrifugal force only exists while the object is moving in the circular path while it counters the centripetal force; as soon as it is released, it disappears.

Here is a nasa site that tries to explain centrifugal force.

Everything from here down is an attempt to clear up centrifugal force. Skip it if you wish.

Common misuse: the "centrifugal pump": this pump takes advantage of the inertia of fluids. A motor spins and propels he fluid into a pipe. The fluid moves into the pipe much like the rock that was twirling on the string: it moves along in a straight line from where it leaves the pump, NOT outward from the string holder.

Please look and see how this pump works... water is sucked in due to the spinning gear. Then it is expelled throught the only other opening.

HERE is a short movie of a hammer tosser. Note that the hammer flies at 90° from where he releases, then it keeps going straight. Depending on your movie viewer software, you can adjust the frame speed or move a bar to show which frames you want to see.
THE HAMMER FLIES WEST BECAUSE IT WAS RELEASED WHILE THE CORD POINTED NORTH!

Note that this fan has its opening aiming at 90° from the top of the circle, or mathematically speaking: the exit flow aims along a tangent to the radius. It does not just aim outward from the fan blades.