Object’s in Motion Study Guide – Chapter 4

1. Define and explain the difference between speed and velocity.

2. Define and explain the difference between displacement and distance.

3. What is acceleration?

4. What is the difference between change in velocity and constant velocity. Sketch X-t and v-t graph as example.

5. Displacement __________ ___________ _______________6. Distance ___________ ___________ _______________

7. Acceleration _______ ___________ _______________

8. Constant velocity _______ ___________ _______________

9. Change in velocity _______ ___________ _______________

10. Speed _______ ___________ _______________

11. Time _______ ___________ _______________

12. Constant acceleration _______ ___________ _______________

13. There are two equations we use when we have constant acceleration – horizontal or free fall (vertical) motion. Write the two equations.

14. What is the equations for constant velocity?

15. Displacement example problem: A truck moves 70 m east, then moves 120 m west, and finally moves east again a distance of 90 m. If east is chosen as the positive direction, what is the truck's resultant displacement?

a) 40 mb) -40 mc) 280 md) -280 m

SI unit Vector Scalar

Determine the SI unit for each quantity and determine if it is a vector or scalar quantity.

16. If a car is moving southward with a constant velocity, what direction is its velocity?

17. If a car starts from rest then reaches a max velocity of 60 mi/hr in the positive direction, which direction is its acceleration?

18. If a car starts from rest then reaches a max velocity of 60 mi/hr in the negative direction, which direction is its acceleration?

19. If a car is traveling in the positive direction with a velocity of 60 mi/hr before coming to rest, which direction is its acceleration?

20. How can a car be traveling at a constant speed but have a change in velocity?

21. What is a free falling object? How is it different than object traveling in the horizontal direction?

22. If a ball is tossed in the air, at max height, what is its acceleration and velocity?

23. A ball falling from a roof will have a positive or negative velocity? What is its acceleration?

24. A car is traveling with a constant velocity northbound. What is its average velocity if it travels 200 mi in 2.3 hour. Final answer in sig figs. Don’t forget units.

25. A car is traveling with a speed of 45 m/s southbound. How far di the car travel in 245 seconds? Final answer in sig figs. Don’t forget units.

Problem Solving

Problem Solving27. A penny is dropped from a building in 34.2 seconds. How tall is the building?

28. You drop a water balloon from a building. It takes the balloon 0.89s to reach the ground. How far did you drop it.

29. A car starting from rest accelerates in the positive direction at 2.5 m/s2 in 1.2s. How far di the car travel during this time?

30. A car starting from rest reaches a max velocity of 55mi/hr in 0.22 hr. What is the car’s acceleration during the 0.22hr?

31. A dog runs in positive direction with initial speed of 2.3m/s. In 6.0s it reaches a speed of 4.3m/s, what is the dog’s acceleration?

32. How many hours in a minute?33. How many seconds in an hour?34. How many kilometers in a meter?35. How many cm in a meter?

36. Below is two position (x) vs. Time (t) graph. Units are meters and seconds respectively. Answer the following questions for each graph:

a. Is the object traveling in the positive or negative direction. b. What is the velocity (slope) of each graph?c. What is the acceleration of each graph?

31. Below is two position (x) vs. Time (t) graph. Units are meters and seconds respectively. Answer the following questions for each graph:

a. Is the object traveling in the positive or negative direction. b. Does the object have constant velocity or constant acceleration?