This document provides an introduction to periodic and circular motion. It discusses key concepts such as centripetal acceleration, centripetal force, and centrifugal force. Centripetal acceleration is the acceleration toward the center required to maintain circular motion. Centripetal force is the force providing the necessary centripetal acceleration, given by Fc = mv2/r. Centrifugal force is a fictional outward force felt in a rotating reference frame.
2. Periodic Motion: a comparison Projectile motion was an object going up and coming down, ONCE! -vs.- Periodic motion is a repeating motion, that can be described with Newtonian physics and our kinematics equations.
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4. The human body cannot sense constant velocity… But it has a great ability to sense small shifts in acceleration .
5. I. Circular Motion Remember that acceleration is a change in speed or direction.. So an object spinning in a circle can have constant speed, but since its direction is changing, the velocity is changing and therefore acceleration. In circular motion its called Centripetal Acceleration . * Centripeta l: meaning center seeking or towards the center.
6. Centripetal acceleration It it a difficult derivation, that I do not want to spend time on, but based on taking two points very close together on a circle (that can be connected by a tangent), we get… a c = v = v 2 t r
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9. Why use this for velocity? This makes it easier to determine the velocity of the object, since distance and time can be measured without interfering in the motion.
10. Put these two equations together. (derive as a class)