Centripetal Acceleration Uniform Circular Motion Uniform circular motion
- Slides: 18
Centripetal Acceleration
Uniform Circular Motion Uniform circular motion is the motion of an object in a circle with a constant or uniform speed
Objects moving in uniform circular motion will have a constant speed. But does this mean that they will have a constant velocity?
No. Because…
Tangential Velocity The best word that can be used to describe the direction of the velocity vector is the word tangential.
Calculation of Velocity
Centripetal Force Any object moving in a circle (or along a circular path) experiences a centripetal force. Centripetal means moving or directed toward a center or axis. “Center Seeking”
Centripetal Force The word centripetal is merely an adjective used to describe the direction of the force. We are not introducing a new type of force but rather describing the direction of the net force acting upon the object that moves in the circle.
Centripetal Force Centripetal force on an object depends on: The object’s mass - more mass means more force. The object’s speed - more speed means more force. And…
Centripetal Force The centripetal force on an object also depends on: The object’s distance from the axis (radius). If linear velocity is held constant, more distance requires less force. If rotational velocity is held constant, more distance requires more force.
Examples:
“Centrifugal Force” “Centrifugal force” is a fictitious force - it is not an interaction between 2 objects, and therefore not a real force. Nothing pulls an object away from the center of the circle.
“Centrifugal Force” What is erroneously attributed to “centrifugal force” is actually the action of the object’s inertia whatever velocity it has (speed + direction) it wants to keep.
Centripetal Acceleration An object moving in a circle is experiencing an acceleration. Even if moving around the perimeter of the circle with a constant speed, there is still a change in velocity and subsequently an acceleration.
WHY?
Centripetal Acceleration This acceleration is directed towards the center of the circle.
Centripetal Acceleration
A 900 -kg car moving at 10 m/s takes a turn around a circle with a radius of 25. 0 m. Determine the acceleration and the net force acting upon the car.