Physics Mid-Term Review

37. Pressure in a fluid system can be calculate using the following formulas: a) P = F - A b) P = F x A c) P = x h d) P = / h

C

41.What is the absolute pressure in a perfect vacuum? a) infinitely large b) impossible to measure c) zero d) 14.7 lb/in2

C

. A pneumatic fluid system uses a ________ as the fluid . a) gas b) liquid c) solid d) plasma

A

10. What type of force(s) allows you to move a lawn mower at a constant speed? a) balanced b) unbalanced c) net force of zero. d) all of the above.

A

13. From an astronaut's experiences in space and on the earth's surface, which of the following statements is true? a) Mass is constant, but weight changes with location. b) Mass and weight are constant when location changes. c) Weight is constant, but mass changes with location. d) Weight and mass change with location.

A

28. What is the density of a substance that has a mass of 113.5 g and a volume of 28.5 cm3? a) 3.98 g/cm3 b) 3,234.75 g/cm3 c) 85 g/cm3 d) 0.25 g/cm3

A

36. The prime mover is a fluid system is a) pressure difference. b) a force. c) density. d) specific gravity.

A

48. What is the maximum voltage from a D-cell (typical flashlight cell)? a) 1.5 volts b) 0.75 volts c) 2.0 volts d) 12 volts

A

5. There are two types of electricity: direct current and alternating current. In which does electricity move in only one direction? a) direct current b) alternating current c) both d) neither

A

5. Which of the following is a list of only vector quantities? a) force, weight, and velocity. b) force, speed, and time. c) velocity, displacement, and temperature. d) volume, pressure, and force.

A

56. When connecting cells in series the voltages add (like forces acting in the same direction) when the cell terminals are connected a) positive to negative b) positive to positive, negative to negative

A

57. In a Series Circuit the Total Voltage from the voltage source is a) equal to the sum of the voltages for each load. b) equal to the product of the voltages for each load. c) equal to the voltage measured at each load. d) equal to the difference in voltage measured at each load.

A

59. In a series circuit, different loads a) receive different amounts of voltage. b) always receive the same voltage. c) are "brighter" than in parallel circuits. d) none of the above.

A

61. Force is to Mechanical System, as __________ is to electrical systems. a) voltage b) current c) frequency d) resistance

A

62. The negative electrode or terminal of a cell is called the a) anode b) ground c) cathode d) load

A

63. An device added to an electrical circuit with the designed purpose of using electrical energy is called

A load

12. An arrow is commonly used to represent a vector. The length of the arrow indicates the a) direction of the quantity. b) magnitude of the quantity. c) direction and magnitude of the quantity. d) none of the above.

B

15. Which of the following is not a force? a) weight b) mass c) horizontal push d) lift or upward pull

B

26. A hydraulic fluid system uses a ________ as the fluid. a) gas b) liquid c) solid d) plasma

B

38. Fluids always flow from ______ to ______ pressure points. a) low, high b) high, low c) negative to positive d) warm, cold

B

39. A tire pressure gauge reads 60 psi and the absolute pressure equals 74.2 psi. What is the value of the atmospheric pressure (air pressure)? a) 134.2 psi b) 14.2 psi c) -14.2 psi d) unknown

B

42. The control elements in an electrical circuit are most commonly a) light bulbs b) switches c) batteries d) wires

B

53. When two similar lamps are connected in series to a 12-volt power supply, what is the voltage drop across each lamp is a) 12 volts. b) 6 volts. c) 24 volts. d) none of these.

B

54. Which instrument below does not measures the voltage in an electrical circuit? a) analog ammeter b) oscilloscope c) analog multimeter c) panel voltmeter

B

55. If twoCell, one with a voltage of 6-Volts and the other rated at 1.5 volts, are connected as shown, what would be the voltage measured by the voltmeter? a) 2-volts b) 7.5-volts c) 4.5-volts d) 10.5-volts e) none of these

B

6. When an object is observed to change speed or direction, we know a(an) _______ force is acting upon it. a) a zero net b) unbalance c) balanced d) balanced and unbalanced

B

60. What is the freq uency of DC current in North America? a) 12 Hz b) 60 Hz c) 110 Hz d) 220 Hz e) none of these

B

8. When two forces act upon a single object, the resultant force (net force) is determined by subtracting the two forces only when a) they act at an angle of 90o to each other. b) they act in opposite direction to each other. c) they act in the same direction. d) all of the above.

B

9. Force is measured in units of a) pounds or meters. b) newtons or pounds. c) angles or degrees. d) joules or newtons.

B

When using a voltmeter to measure voltage in a circuit a) the circuit must be broken to add the meter in series. b) the circuit is not broken, a parallel connection is made with the voltmeter. c) the voltage source must be removed from the circuit. d) the lowest range of voltages are selected on the multimeter.

B

1. A force is .... a) a scalar quantity. b) measured in meters. c) a vector quantity. d) mass divided by volume.

C

11. A vector is any quantity that has a) magnitude only. b) direction only. c) magnitude and direction. d) neither magnitude nor direction.

C

2. A force can do all of the following But .... a) start an object moving or speed it up. b) slow an object or cause it to stop. c) change the mass of an object. d) change the direction of a moving object.

C

27. What property of a substance determine whether it floats or sinks? a) weight b) volume c) density d) pressure

C

3. A push or pull in a given direction is known as a a) pressure difference. b) scalar. c) force. d) torque.

C

30. Which of these instruments is able to measure specific gravity? a) sling psychrometer b) manometer c) hydrometer d) spring balance

C

44. A general electrical system should include a voltage source, conductors, control elements and .... a) lamps. b) circuit breakers. c) electrical loads. d) electric motors.

C

47. What is the difference between a Primary Cell and a Secondary Cell? a) Primary Cells where invented before Secondary Cells. b) Primary Cells produce direct current, Secondary Cells produce alternating current. c) Primary Cells are not easily recharged, Secondary Cells are easily recharged. d) Primary Cells produce higher voltage than Secondary Cells.

C

51. Frequency is measured in cycles per second or hertz. In North America, AC voltage alternates with a frequency of a) 220 hertz. b) 110 hertz. c) 60 hertz. d) 115 hertz.

C

52. In all electrical systems, the prime mover that acts like a force is a) current b) resistance c) voltage d) frequency

C

When all the forces acting on a airplane during flight are balanced the airplane will a) fall toward the ground and gain speed. b) gain altitude and decrease speed. c) maintain constant speed and altitude. d) decrease speed and altitude.

C

14. To calculate torque in a rotational mechanical system you must a) divide the force by the lever arm length b) multiply force and angle of rotation. c) divide force by the angle of rotation. d) multiply force and lever arm length.

D

29. What is the specific gravity of a substance that has a density of 4.6 g/cm3. a) 4.6 g/cm3 b) 2.3 g/cm3 c) 2.3 d) 4.6

D

31. A buoyant force is present when an object floats in a) only water b) only air c) outer space d) fluids

D

32. Which of the following is NOT a pressure unit? a) mm of Hg. b) psi. c) inches of H2O d) lb/ft3.

D

33. Which of the following is a correct value for 1 atmosphere of pressure? a) 14.7 lb/ft2 b) 14.7 lb/in2 c) 14.7 inches of Hg d) 14.7 N/m2

D

34. The pressure of the atmosphere is produced by the a) flow of the air above us. b) volume of the air above us. c) movement of the air around us. d) height and weight density of the air above us.

D

35. The weight density of a fluid is 3.0 lb/ft3. The fluid fills a rectangular container that is 5 feet high, 2 feet wide and 4 feet long. What is the pressure on the floor of the container? a) 60 lb/ft2 b) 120 lb/ft2 c) 24 lb/ft2 d) 15 lb/ft2

D

4. Which of the following is not used to measure a force? a) spring scale. b) bathroom scale. c) platform balance. d) all of the above. e) none of the above

D

40. A net pressure a) can cause a fluid to move or flow. b) can cause a change in the shape of a container. c) is measured in units of psi or N/m2. d) all of the above. e) none of the above

D

43. Which of the following is a common load found in electrical circuits? a) a switch b) a dry cell c) wires d) a lamp

D

46. Which of these voltage sources produce only direct current? a) loads b) switches c) generators d) thermocouples

D

49. DC power sources normally have two electrodes, one positive and the other negative. Sometimes they are color coded with a) red as negative, black positive. b) black as negative, and red positive. c) white as negative, and red as positive. d) black as negative, and white as positive.

D

50. When DC power sources are connected to produce higher voltage they are connected in a) series; positive terminal from one source to the positive terminal of the other. b) parallel; positive terminal from one source to the others positive terminal. c) parallel; positive terminal from one source to the others negative terminal. d) series; positive terminal from one source to the negative terminal of the other.

D

___ 16. torque a) Has only magnitude. ___ 17. vector b) Effect of gravity on an object. ___ 18. scalar c) Quantity of matter in an object. ___ 19. weight d) Forcelike quantity in a rotational system. ___ 20. mass e) a push or a pull in a straight line. ___21. lever arm a) loosen a bolt. ___ 22. counterclockwise turn b) distance from an axis to the point of force. ___ 23. equals balanced forces c) zero net force.

D E A B C C B A

24. A fluid is a .... a) gas. b) liquid. c) solid. d) plasma. e) gas or liquid.

E