Average Velocity Unit 8.2

scalar vector position is changing distance d Dd time Dt time Dt m/s Ddisplacement time Dt time Dt m/s km/h

5s – 7s, 14s – 16s 18s – 19s 0s – 2s, 7s – 12s, 16s – 18s, 19s- 20s 2s – 5s, 12s – 14s 2s – 5s, 12s – 14s

Practice: Calculate average velocity. What is the average velocity of a dog that takes 4.0 s to run forward 14 m? A boat travels 280 m east in a time of 120 s. What is the boat’s average velocity?

Practice: Calculate displacement. What is the displacement of a bicycle that travels 8.0 m/s [N] for 15 s? A person, originally at the starting line, runs west at 6.5 m/s. What is the runner’s displacement after 12 s?

Practice: Calculate the time interval How long would it take a cat walking north at 0.80 m/s to travel 12 m north? A car is driving forward at 15 m/s. How long would it take this car to pass through an intersection that is 11 m long?

Practice: Try the following unit conversion problems. Convert 95 km/h to m/s. A truck’s displacement is 45 km north after driving for 1.3 h. What was the truck’s average velocity in km/h and m/s?

5.5 s 2.0 + 1.5 = 3.5 m 3.5/5.5 = 0.64 m/s 0.5/5.5 = 0.091 m/s [right] +0.5 m or 0.5 m [right]