Chapter 12 Section 1 Part 2 Velocity Velocity

Chapter 12 Section 1 Part 2

Velocity • Velocity is the speed of an object in a particular direction. Example: an airplane’s velocity is 600 km/hr south Velocity changes when an object’s speed or direction changes.

Practice • Which of the following are examples of velocity? • A. 25 m/s forward • B. 1, 500 km/h • C. 55 m/h south • D. 33 m/h • Answer: A & C

Acceleration • Acceleration tells you how fast velocity changes. • Acceleration occurs when an object: 1. Speeds up 2. Slows down 3. Changes direction

Acceleration Continued • Positive acceleration = velocity increases • Negative acceleration = velocity decreases • Acceleration = final velocity - initial velocity final time - initial time Example While riding your bicycle you go from a speed of 0 m/s to a speed of 5 m/s in 5 seconds. What is your acceleration? • vf - vi = 5 m/s - 0 m/s = 1 m/s/s tf - ti 5 s

Circular Motion • An object traveling in a circle is always changing its direction so acceleration is occurring. • Centripetal acceleration is the acceleration that occurs in a circular motion.

Acceleration on a Graph • Acceleration on a graph is velocity vs time.

Let’s Try it • Quick Lab pg. 342 - Graphing Acceleration • http: //www. thetravelalmanac. com/lists/vide os/animals-speed. htm