Conceptual Physics Daily 10

1. Conceptual PhysicsDaily 10 Adapted from physicsclassroom.com

2. Which of these is a scientific hypothesis? a. Atoms are the smallest particle of matter that exists. b. Albert Einstein is the greatest scientist of the twentieth century. c. The universe is surrounded by a second universe that cannot be seen. SCSh7, SCSh7e,SCSh8,SCSh8a

3. Which of these is a scientific hypothesis? a. Atoms are the smallest particle of matter that exists. b. Albert Einstein is the greatest scientist of the twentieth century. c. The universe is surrounded by a second universe that cannot be seen. SCSh7, SCSh7e,SCSh8,SCSh8a

4. 2. To test a scientific hypothesis you would: • Use the results of only the experiment that confirm the hypothesis. b. Set up an experiment and look at the results. c. Find the best result and report only that result. d. Set up many experiments and look at the results. SCSh7, SCSh7e,SCSh8,SCSh8a

5. 2. To test a scientific hypothesis you would: • Use the results of only the experiment that confirm the hypothesis. b. Set up an experiment and look at the results. c. Find the best result and report only that result. d. Set up many experiments and look at the results. SCSh7, SCSh7e,SCSh8,SCSh8a

6. 3. A scientific hypothesis may turn out to be right or it may turn out to be wrong. If it is a valid hypothesis, there must be a test to prove it a. right b. wrong SCSh7, SCSh7e,SCSh8,SCSh8a

7. 3. A scientific hypothesis may turn out to be right or it may turn out to be wrong. If it is a valid hypothesis, there must be a test to prove it • right • wrong SCSh7, SCSh7e,SCSh8,SCSh8a

8. 4. The difference between a hypothesis and a theory is that a hypothesis is • never true whereas a theory is always true • true whereas a theory is not true • never true whereas a theory is sometimes true • an educated guess whereas a theory has been tested successfully many times SCSh7, SCSh7e,SCSh8,SCSh8a

9. 4. The difference between a hypothesis and a theory is that a hypothesis is • never true whereas a theory is always true • true whereas a theory is not true • never true whereas a theory is sometimes true d.an educated guess whereas a theory has been tested successfully many times SCSh7, SCSh7e,SCSh8,SCSh8a

10. 5. A scalar quantity has • only direction • only magnitude • both magnitude and direction • neither magnitude or direction SP1b,SP1b,SP1f

11. 5. A scalar quantity has • only direction b. only magnitude • both magnitude and direction • neither magnitude or direction SP1b,SP1b,SP1f

12. 6. What is needed to describe a vector quantity? • only magnitude • only direction • both magnitude and direction • Neither magnitude nor direction SP1b,SP1b,SP1f

13. 6. What is needed to describe a vector quantity? • only magnitude • only direction • both magnitude and direction • Neither magnitude nor direction SP1b,SP1b,SP1f

14. 7. Equilibrium occurs when • all the forces acting on an object are balanced. • the sum of the + forces equals the sum of the – forces. • the net force on the object is zero. • the sum of the upward forces equals the sum of the downward forces. • all of the above. SP1b,SP1b,SP1f

15. 7. Equilibrium occurs when • all the forces acting on an object are balanced. • the sum of the + forces equals the sum of the – forces. • the net force on the object is zero. • the sum of the upward forces equals the sum of the downward forces. • all of the above. SP1b,SP1b,SP1f

16. 8. What is the maximum resultant possible when adding a 3N force and a 5N force? • 3N • 5N • 8N • 2N • 15N SP1b,SP1b,SP1f

17. 8. What is the maximum resultant possible when adding a 3N force and a 5N force? • 3N • 5N • 8N • 2N • 15N SP1b,SP1b,SP1f

18. 9. What is the minimum resultant possible when adding a 3N force and a 5N force? • 3N • 5N • 8N • 2N • 15N SP1b,SP1b,SP1f

19. 9. What is the minimum resultant possible when adding a 3N force and a 5N force? • 3N • 5N • 8N • 2N • 15N SP1b,SP1b,SP1f

20. 10. A barge is being pulled along a canal by two ropes that make equal angles with the direction in which the barge points. Assuming the two pulls on the barge are equal, in what direction does the barge move? • It oscillates back and forth between the two banks. • It moves straight forward. • It moves in the direction of the resultant force on it. • Both a and b • Both b and c SP1b,SP1b,SP1f

21. 10. A barge is being pulled along a canal by two ropes that make equal angles with the direction in which the barge points. Assuming the two pulls on the barge are equal, in what direction does the barge move? • It oscillates back and forth between the two banks. • It moves straight forward. • It moves in the direction of the resultant force on it. • Both a and b • Both b and c SP1b,SP1b,SP1f

22. 11. The astronomer Copernicus publicly stated in the 1500s that Earth a. does not move b. revolves around the sun. c. is slowing down. d. moves in a straight line. e. is the center of the solar system. SP1d

23. 11. The astronomer Copernicus publicly stated in the 1500s that Earth a. does not move b. revolves around the sun. c. is slowing down. d. moves in a straight line. e. is the center of the solar system. SP1d

24. 12.The law of inertia applies to a. objects at rest. b. moving objects. c. both moving and nonmoving objects. SP1d

25. 12.The law of inertia applies to a. objects at rest. b. moving objects. c. both moving and nonmoving objects. SP1d

26. 13. Friction a. comes from microscopic bumps that act as obstructions to the object's motion. b. is the name given to the force acting between surfaces sliding past one another. c. acts in a direction that opposes the motion of an object. d. all of the above e. none of the above

27. 13. Friction a. comes from microscopic bumps that act as obstructions to the object's motion. b. is the name given to the force acting between surfaces sliding past one another. c. acts in a direction that opposes the motion of an object. d. all of the above e. none of the above SP1d

28. 14. Which has more mass, a kilogram of feathers or a kilogram of iron? • The feathers • The iron c. Neither—they both have the same mass. SP1d

29. 14. Which has more mass, a kilogram of feathers or a kilogram of iron? • The feathers • The iron c. Neither—they both have the same mass. SP1d

30. 15. How much does a 3.0-kg bag of bolts weigh? a.7.2 N b.14.4 N c.22.8 N d.29.4 N e.58.8 N SP1d

31. 15. How much does a 3.0-kg bag of bolts weigh? a.7.2 N b.14.4 N c.22.8 N d.29.4 N e.58.8 N SP1d

32. 16. On the surface of the Moon, a ball is thrown straight up with an initial velocity. The ball has a constant acceleration due to the Moon’s gravity. On a graph of the ball’s velocity versus time, which of the following would represent the ball at its highest point above the Moon’s surface? A. when the velocity is equal to 0 m/s B. when the velocity is equal to 1.6 m/s C. when the velocity has its greatest value D. when the velocity has its most negative value SPS8 a

33. 16. On the surface of the Moon, a ball is thrown straight up with an initial velocity. The ball has a constant acceleration due to the Moon’s gravity. On a graph of the ball’s velocity versus time, which of the following would represent the ball at its highest point above the Moon’s surface? A. when the velocity is equal to 0 m/s B. when the velocity is equal to 1.6 m/s C. when the velocity has its greatest value D. when the velocity has its most negative value SPS8 a

34. 17. A rocket is launched at a speed of 10 kilometers per second. How far will it travel in 1/2 minute? A. 300 km B. 5 km C. 3000 m D. 600 m SPS8 a

35. 17. A rocket is launched at a speed of 10 kilometers per second. How far will it travel in 1/2 minute? A. 300 km B. 5 km C. 3000 m D. 600 m SPS8 a

36. 18. Speed is • a measure of how fast something is moving. • always measured in terms of a unit of distance divided by a unit of time. • the distance covered per unit time. • all of the above. • none of the above. SP1a,b

37. 18. Speed is • a measure of how fast something is moving. • always measured in terms of a unit of distance divided by a unit of time. • the distance covered per unit time. • all of the above. • none of the above. SP1a,b

38. 19. One possible unit of speed is • miles per hour. • light years per century. • kilometers per hour. • all of the above • none of the above. SP1a,b

39. 19. One possible unit of speed is • miles per hour. • light years per century. • kilometers per hour. • all of the above • none of the above. SP1a,b

40. 20. An elevator in an office building completed the following trips: • 1st floor to 8th floor • 8th floor to 4th floor • 4th floor to 13th floor The distance between each floor of the office building is 3.0 m. Which table shows the total distance traveled and displacement of the elevator? SP1a,b

41. SP1a,b

42. 21. The table below shows the time it takes four cars to go from 0 to 60 km/h. Based on the information given, which of the following quantities can be compared for the four cars? A. average acceleration B. instantaneous speed C. stopping distance D. stopping time SP1a,b

43. 21. The table below shows the time it takes four cars to go from 0 to 60 km/h. Based on the information given, which of the following quantities can be compared for the four cars? A. average acceleration B. instantaneous speed C. stopping distance D. stopping time SP1a,b

44. 22. If an object has an acceleration • of 0 m/s2, then one can be sure • that the object is not ____. • moving • changing position • changing velocity • SP1a,b

45. 22. If an object has an acceleration • of 0 m/s2, then one can be sure • that the object is not ____. • moving • changing position • changing velocity • SP1a,b

46. 23. Which one of the following statements is NOT true of a free-falling object? An object in a state of free fall ____. a. falls with a constant speed of -10 m/s. b. falls with a acceleration of -10 m/s/s. c. falls under the sole influence of gravity. d. falls with downward acceleration which has a constant magnitude. SP1a,b

47. 23. Which one of the following statements is NOT true of a free-falling object? An object in a state of free fall ____. a. falls with a constant speed of -10 m/s. b. falls with a acceleration of -10 m/s/s. c. falls under the sole influence of gravity. d. falls with downward acceleration which has a constant magnitude. SP1a,b

48. 24. Which of the following statements about free fall and the acceleration of gravity are TRUE? List all that apply. • a. An object that is free-falling is acted • upon by the force of gravity alone. • b. A falling skydiver which has reached • terminal velocity is considered to be • in a state of free fall. • c. A ball is thrown upwards and is rising towards its peak. As it rises upwards, it is NOTconsidered to be in a state of free fall. SP1a,b

49. d. An object in free fall experiences an acceleration which is independent of the mass of the object. e. A ball is thrown upwards, rises to its peak and eventually falls back to the original height. As the ball rises, its acceleration is upwards; as it falls, its acceleration is downwards. SP1a,b

50. f. A ball is thrown upwards, rises to its peak and eventually falls back to the original height. The speed at which it is launched equals the speed at which it lands. (Assume negligible air resistance.) g. A very massive object will free fall at the same rate of acceleration as a less massive object. SP1a,b