1. 2011 Midterm Review Physics Ms. Allison

2. a.more. b.unchanged. c.less. An airplane flying into a head wind loses ground speed, and an airplane flying with the wind gains ground speed. If an airplane flies at right angles to the wind, then ground speed is

3. Answer An airplane flying into a head wind loses ground speed, and an airplane flying with the wind gains ground speed. If an airplane flies at right angles to the wind, then ground speed is a.more.

4. a.in the direction of motion. b.opposite its velocity. c.directed downward. d.directed upward. A ball tossed vertically upward rises, reaches its highest point, and then falls back to its starting point. During this time the acceleration of the ball is always

5. c.directed downward. A ball tossed vertically upward rises, reaches its highest point, and then falls back to its starting point. During this time the acceleration of the ball is always Answer

6. An archer shoots an arrow. Consider the action force to be the bowstring against the arrow. The reaction to this force is the a.arrow's push against the bowstring. b.weight of the arrow. c.friction of the ground against the archer's feet. d.air resistance against the bow.

7. a.arrow's push against the bowstring. An archer shoots an arrow. Consider the action force to be the bowstring against the arrow. The reaction to this force is the Answer

8. a.Linear speed b.Tangential speed c.Rotational speed d.Centripetal force. A car driving straight down the street has

9. a.Linear speed A car driving straight down the street has Answer

10. What do we know about energy based on the conservation of energy?

11. According to the conservation of energy, we know the energy is neither loss or created only transferred from one form to another. Answer

12. a.that changes as a person bends over. b.that is fixed, though different for different people. c.that is always directly behind the belly button. d.none of the above The center of gravity of a human body is located at a point

13. Answer a.that changes as a person bends over. The center of gravity of a human body is located at a point

14. a.The inside horse b.The outside horse c.Neither—they both have the same tangential speed. Which has greater tangential speed, a horse near the outside rail of a merry-go- round or a horse near the inside rail?

15. Answer b.The outside horse Which has greater tangential speed, a horse near the outside rail of a merry-go- round or a horse near the inside rail?

16. a.The inside horse b.The outside horse c.Neither—they both have the same rotational speed. Which has greater rotational speed, a horse near the outside rail of a merry-go- round or a horse near the inside rail?

17. Answer c.Neither—they both have the same rotational speed. Which has greater rotational speed, a horse near the outside rail of a merry-go- round or a horse near the inside rail?

18. a.direction. b.magnitude. c.time. d.color. A scalar is a quantity that has

19. Answer b.magnitude. A scalar is a quantity that has

20. a.The mounted tire, provided the tire is more massive than the rim b.The tire alone, provided it is as heavy as the rim c.The tire alone, regardless of its weight d.The mounted tire, regardless of its weight Which rolls to the bottom of a hill sooner, a car tire alone or the same tire mounted on a rim?

21. Answer c.The tire alone, regardless of its weight Which rolls to the bottom of a hill sooner, a car tire alone or the same tire mounted on a rim?

22. What has more influence on kinetic energy; mass or velocity?

23. Answer What has more influence on kinetic energy; mass or velocity? Velocity because it is squared in the kinetic energy equation

24. What is the relationship between kinetic energy and conservation of energy?

25. Answer What is the relationship between kinetic energy and conservation of energy? Kinetic energy is the energy of motion. When one moving object hits another, the energy is transferred between the objects since energy cannot be creates nor destroyed according the law of the conservation of energy.

26. How fast does Kenny run the 100 m dash if he crosses the finish line in 10 s?

27. Answer Known d = 100m t = 10s Unknown v Equation v = d/t Solve v = d/t = 100 m 10s = 100 m/s

28. About how tall is a tree, if it takes 1.2s for an apple to fall to the ground from the very top branch?

29. Answer Known t =1.2s g = 10m/s 2 v o = 0 Unknown d Equation d = v o t + ½ gt 2 Solve d = v o t + ½ gt 2 = (0)(1.2s) + ½(10m/s 2 )(1.2s) 2 = ½(10m/s 2 )(1.2s) 2 = ½(10m/s 2 )(1.44s 2 ) = (5m/s 2 ) (1.44s 2 ) = 7.2 m

30. Michael is 75kg and runs up the a 5 m high hill in 25s. What is his power input?

31. Answer Known m = 75kg d = 5m t = 25s Unknown Power Equation Power = W/t Solve Power = W/t = Fd/t (remember Force times distance is work) = mgd/t (remember Force is mass times gravity) = (75kg)(10m/s 2 )(5m) 25s = 3750 kg m 2 /s 2 25s = 150 W