Forces and Motion Review

1. Forces and Motion Review Balanced and Unbalanced Forces Mrs. Bixler-Zalesinsky

2. Use this picture to answer the following questions.

3. 1. • What forces are acting on the apple when it is at rest on the books? • a. gravity b. applied • c. normal d. both a and b

4. 2. • After a student’s force acts on the objects in the figure to remove the books quickly and causing the apple to fall, which object(s) did NOT accelerated? • a. apple b. books • c. table d. student

5. 3. • When the student’s force acts on the diagram above, the main force acting on the apple, which causes it to fall, is which of the following? • a. gravitational b. frictional • c. air resistance d. normal

6. 4. • When the force of the student acted on the figure above, which objects had velocity greater than zero? • a. table • b. apple • c. books • d. both b and c

7. 5. • A student collects and analyzes data from the motion of the apple from the time it rests atop the books until it is just above the floor. Create a distance (m) vs. time (s) graph that most closely represents the motion of the apple for this brief period of time.

8. 6. • The student collects and analyzes data of the motion of the apple from the time it rests atop the books until it is just above the floor. Create a speed (m/s) vs. time (s) graph that most closely represents the motion of the apple for this brief period of time.

9. 7. – 9. Imagine a marble is going to roll off of a book on an inclined plane onto a stack of dominos like the picture below.

10. 7. • In order to find the force that hit the domino, you need to know what measurements? • a. mass of the marble • b. acceleration of the marble • c. mass of the domino • d. both a and b

11. 8. • 8. To find the acceleration of the marble, you need to know which measurements? • a. mass of the marble • b. change in the velocity of the marble • c. time it took to travel • d. both b and c

12. 9. • To find the velocity of the marble, you need to know which measurements? • a. mass of the marble • b. distance of wood • c. time it took to travel • d. both b and c

13. 10. • In some situations, friction is desirable, which of the following are situations where friction is desirable? • a. turning car • b. sledding • c. skiing • d. both b and c

14. 11. • In some situations, the effect of friction is undesirable and needs to be minimized. In which of the situations listed below would friction be undesirable? • a. moving machine parts rubbing together • b. walking • c. warming hands • d. braking

15. 12. • In which of the following does torque play a part? • a. opening a flip-top can • b. digging and lifting a shovelful of dirt • c. pedaling a bicycle • d. all of the above

16. 13. • Which of the following parts of a human body does NOT contribute to maintaining balance? • a. muscle and joints • b. heart • c. inner ear • d. eyes

17. 14. • The difference between speed and velocity is that velocity includes • a. direction b. time • c. distance d. weight

18. 15. • Which is an example of kinetic friction? • friction between a car’s windshield and the air as you drive into the wind • friction between your shoes and the ground when you stand still • friction between a sticky note and the page of a book as it marks your place • friction between your skin and a pencil as it rests in your palm

19. 16. • A race car travels around a circular track. Explain why the car is accelerating even though the driver maintains a constant speed. • Your foot pushes down on the accelerator, but you just don’t feel it. • You are constantly changing direction. • You are speeding up. • You are slowing down

20. 17. • An airplane is flying at 635 miles per hour at an altitude of 35,000 feet. It is currently over Kansas and is approximately 16 minutes ahead of its scheduled arrival time. What is its speed? • 635 miles per hour • 35,000 feet • 16 minutes • Cannot be determined

21. 18. • Displacement • must be in a particular direction • is the change in position of an object • must be the shortest distance possible between two points • all of the above

22. 19. • The similarity between acceleration and velocity is that they both measure the • rate of change of displacement • rate of change of velocity • change over time • both a and b

23. 20. • If the net force acting on a stationary object is zero, then the object will • accelerate in the direction of the strongest force • remain at rest • begin moving backwards • decelerate at a steady rate of speed

24. 21. • In order to determine if an object is moving, you must observe the object in relation to a ___. • a. curved path • b. moving object • c. reference point • d. force

25. Extended Response You may want to complete your pre-writing activities outside of class; however, nothing can be brought into the test!

26. 22. • Michael started piling books on a small table. Eventually the table broke. • Which arrow represents the force of gravity? (2 pts.) • Which arrow represents the force of the table on the books? (2 pts.) • Explain why the table eventually broke. (2 pts.)

27. 23. • Newton’s second law of motion states the relationship between force, mass, and acceleration as F = ma. According to this law, what happens to the acceleration of a given object with constant mass when the force acting upon it is increased, Explain your answer. (2 pts.)