Accelerated Motion

1. Accelerated Motion Chapter 3

2. Acceleration Section 3-1

3. Changing Velocity • Uniform motion is smooth and unchanging, non-uniform motion causes the feeling ofa push or pull • Motion diagrams for objects with changing velocity will not be constant • Example: page 58

4. Velocity-Time Graph • Velocity-Time Graph – graphs velocity vs. time • Velocity on the Y-axis • Time on the X-axis • Acceleration – the rate at which an objects velocity changes

5. Acceleration • Average Acceleration – the change in velocity divided by the time interval • Instantaneous Acceleration – the change in velocity at an instant in time • Can be found by drawing a tangent line on a velocity-time graph

6. Acceleration on a Motion Diagram • The difference in velocity vectors in a motion diagram will show you the acceleration • Example: page 60

7. Positive and Negative Acceleration • Positive acceleration – an increase in speed in the positive direction, or a decrease in speed in the negative direction • Negative Acceleration – a decrease in speed in the positive direction, an increase in speed in the negative direction • Page 61 Figure 3-7

8. Determining Acceleration from a Velocity-Time Graph • Page 62 Figure 3-8 • Line A – Positive Velocity, 0 Acceleration • Line B – Positive Velocity, Positive Acceleration • Line C – Positive Velocity, Negative Acceleration • Line D – Negative to Positive Velocity, Positive Acceleration • Line E – Negative Velocity, 0 Accleration

9. Calculating Acceleration • The acceleration of an object can be found by the slope of a velocity-time graph • Average Acceleration – equal to the change in velocity, divided by the time it takes to make that change • Example Problem 2