1. LINEAR MOTION Chapter 2

2. Introduction to Motion Scalars and Vectors

3. Motion, Speed and Velocity - 1

4. Motion, Speed and Velocity - 2 ■As we’ve defined it, speed has only one attribute—a magnitude (mathematically it’s what known as a scalar). ■Velocity is speed in a particular direction. So velocity has two attributes—a magnitude and a direction (mathematically it’s what known as a vector). ■If the velocity of an object is constant then both its speed and direction must be constant. ■Similarly if the object’s speed is constant but its direction changes, then its velocity is not constant. (One example is uniform circular motion, which we’ll learn about later in the course.)

5. Acceleration

6. Equations of Motion

7. Example Problem – No. 44

8. Try Problems 45 and 46 ■45. We drive for 1 hour at 20 km/hr. Then we drive for 1 hour at 30 km/hr. What is the average speed over the 2-hour interval? ■46. We drive a distance of 1 km at 20 km/hr. Then we drive an additional distance of 1 km at 30 km/hr. What is our average speed over the 2 km distance?

9. An Example of Linear Motion – Free Fall

10. Apollo 15 – Free Fall on the Moon (1971) Apollo 15

11. Measuring Reaction Time Using Free Fall

12. Human Reaction Time ■Human reaction time ranges from 0.1 to 0.5 seconds with a median around 0.215s

13. Free Fall Problem #1 + -

14. Graphs for Objects in Free Fall* Time (s) Speed (m/s) 00.00 19.80 219.60 329.40 439.20 549.00 658.80 768.60 878.40 988.20 1098.00 Time (s) Distance (m) 00.00 14.90 219.60 344.10 478.40 5122.50 6176.40 7240.10 8313.60 9396.90 10490.00

15. Example Free Fall Problem – No. 47