Like this presentation? Why not share!

# 04-17-08 - Circular Motion

## by wjerlinger on Apr 21, 2008

• 1,223 views

### Views

Total Views
1,223
Views on SlideShare
1,211
Embed Views
12

Likes
0
36
0

### 2 Embeds12

 http://www.nisdtx.org 9 http://www.slideshare.net 3

### Categories

Uploaded via SlideShare as Microsoft PowerPoint

## 04-17-08 - Circular MotionPresentation Transcript

• Uniform Circular Motion
• What is uniform circular motion?
• Movement of an object at constant speed around a circle with a fixed radius
• Can the velocity be accelerated even though it has constant speed?
• Yes, because the velocity may change due to direction. If direction changes and velocity changes then an object can accelerate.
• Describing Circular Motion
• A lower case r represents the position of a vector
• the direction of the vector can change but not its length (length is proportional to magnitude)
• the acceleration of an object in uniform circular motion is always toward the center of the circle, called centripetal acceleration
• Equations
• a c = v 2 /r
• One complete revolution around a circle is called a period
• Symbol is T
• Units are seconds
• an object will travel the distance of the circumference of the circle, which is represented by C = 2πr
• v = 2πr/T
• Combining Equations
• If we substitute the previous formula for v in the original formula for centripetal acceleration we would get
• a c = 4π 2 r/T 2
• Sometimes the force that causes centripetal acceleration is called centripetal force
• Which direction is the net force?
• The same direction as the acceleration
• F net = ma c
• F net = mv 2 /r
• F net = m(4π 2 r/T 2 )
• If you stop the acceleration, what direction will the object move?
• The movement of the object is in the direction the velocity or tangent to the circle.