Final Exam 2003 Physics I

Name:______Period:___ 2010 Physics I Exam Review- 2 nd Semester KEYED Momentum/Impulse/Collisions _B_ 1.. An ice skater initially skating at a velocity of 3 m/s speeds up to a velocity of 5 m/s. The momentum of the skater ______. a. decreases c. remains the same b. increases d. becomes zero

_C___ 2. If a force is exerted on an object, which statement is true? a. A large force always produces a large change in the object’s momentum. b. A large force produces a large change in the object’s momentum only if the force is applied over a very short time interval. c. A small force applied over a long time interval can produce a large change in the object’s momentum. d. A small force produces a large change in the object’s momentum.

__C__ 3. An impulse is applied to stop a moving shopping cart. Increasing the time interval over which the force is applied means that the stopping force is ______. a. greater c. smaller b. unaffected d. the same

___D_ 4. A 6.0 x 10–2 kg tennis ball moves at a velocity of 12 m/s. The ball is struck by a racket, causing it to rebound in the opposite direction at a speed of 18 m/s. What is the change in the ball’s momentum? a. –0.38 kgm/s c. –1.1 kgm/s b. –0.72 kgm/s d. –1.8 kgm/s

___C_ 5. The impulse experienced by a body is equivalent to the body’s change in ______. a. velocity c. momentum b. kinetic energy d. force

____D 6. A 75 kg person walking around a corner bumps into an 80 kg person running around the same corner. The momentum of the 80 kg person ______. a. increases c. remains the same b. decreases d. is conserved

____C 7. A swimmer with a mass of 75 kg dives off a raft with a mass of 500 kg. If the swimmer’s speed is 4 m/s immediately after leaving the raft, what is the speed of the raft? a. 0.2 m/s c. 0.6 m/s b. 0.5 m/s d. 4.0 m/s

____B 8. A bullet with a mass of 5.00 x 10–3 kg is loaded into a gun. The loaded gun has a mass of 0.52 kg. The bullet is fired, causing the empty gun to recoil at a speed of 2.1 m/s. What is the speed of the bullet? a. 48 m/s c. 120 m/s b. 220 m/s d. 360 m/s

____B 9. Two objects move separately after colliding, and both the total momentum and total kinetic energy remain constant. Identify the type of collision. a. elastic c. inelastic b. perfectly elastic d. None of the above

____C 10. A 1.5 x 103 kg truck moving at 15 m/s strikes a 7.5 x 102 kg automobile stopped at a traffic light. The vehicles hook bumpers and skid together after the collision. What is the velocity of the combination? a. 15 m/s c. 10 m/s b. -15 m/s d. -10 m/s SHM and WAVES 12. When a wave crosses a boundary between a string and a rope, which wave properties are changed? (velocity, wavelength and or frequency)__SPEED______and _____WAVELENGTH______Which property is not changed? ______Changed: velocity and wavelength. No change in frequency.

13. When a wave passes from one medium to another and bends, what is this called? refraction

14. When a wave hits a boundary and bounces off, what is this called? reflection 15. You send continuous waves along a string of fixed length. As you decrease frequency, you increase (increase or decrease) wavelength .  so how are frequency and wavelength related? V = f ______INVERSELY______

16. For a TRANSVERSE wave, is the movement of particles Parallel or Perpendicular to the direction of wave propagation? _ Perpendicular ______17. For a LONGITUDINAL wave, is the movement of particles Parallel or Perpendicular to the direction of wave propagation? Parallel

18. On the diagram of the wave, please label the AMPLITUDE, CREST, TROUGH, EQUILIBRIUM, WAVELENGTH

EQUILIBRIUM

19. When a wave hits a FIXED end, like a wall, and is reflected, will it experience a PHASE change? __YES_ 20. When a wave hits a FREE end and is reflected, will it experience a PHASE change? ___NO______

21. What is the primary difference between a Mechanical Wave and an Electromagnetic Wave? ______EM DOES NOT REQUIRE A MEDIUM______

22. An ocean wave has a wavelength of 10 m. A wave passes a fixed location every 2.0 s. What is the speed of the wave? (Find frequency first.) 5 m/s

23. List three examples of simple harmonic motion. PENDULUM AND MASS ON SPRING ( ANY OTHER THAT HAS SIMILAR QUALITIES)

24. When two waves of opposite (crest and trough) amplitudes superpose, the result is called ______destructive ______interference. (constructive or destructive)

25. The Sears Building in Chicago sways back and forth with a frequency of about 0.10 Hz. What is its period of vibration? 10s 26. A mass attached to a spring vibrates back and forth. At the equilibrium position, describe the velocity, acceleration and force. (max or zero) v= max a= 0 F=0 27. A simple pendulum swings in simple harmonic motion. At maximum displacement, describe the velocity, acceleration, and force. (max or zero) v = 0 a = max F=max

28. A sound wave travels at 4500.0 m/s through a steel rod. What is the wavelength if its frequency is 2500.0 Hz? 1.8m

29. Echoes are examples of ___reflection______of sound waves.

30. Sound waves are ____longitudinal__as well as ____mechanical___ waves.

31. A detected change in the frequency of a sound due to a moving source or a moving observer is called the _____doppler effect______.

32. Draw 2 uneven pulses, on the same side of a Slinky, before, during, and after superposition. should have constructive interference creating a larger pulse

33. Draw 2 even pulses, on opposite sides of a Slinky, before, during and after superposition. Should have destructive interference creating a line (pulse seems to disappear) LIGHT 34. List the 7 regions of the EM spectrum from longest wavelength shortest wavelength. RADIO – MICRO – INFRARED – VISIBLE – ULTRAVIOLET – GAMMA

35. The seven colors of the visible light spectrum , in order from 700nm to 400nm, are______RED – ORANGE – YELLOW – GREEN – BLUE – INDIGO – VIOLET _.

8 36. All electromagnetic waves move at _____3 x 10 ______m/s in a vacuum.

37. The fact that light can be polarized shows that light waves are _TRANSVERSE______waves.

38. Label each letter in the diagram. ( normal, incident ray, angle of incidence, etc.)

39. Draw a ray diagram for each of the following convex lenses. Please classify each Image as Real/Virtual, Reduced/Englarged, Upright/Inverted.

REAL, REDUCED, INVERTED

VIRTUAL, ENLARGED,UPRIGHT 40. The bending of light waves from the sun as they pass through our atmosphere is an example of _____REFRACTION__. All angles are measure with respect to the __NORMAL______at all times.

41. If a light ray travels from a more optically dense substance to a less optically dense substance, the light ray will (speed up/slow down) (circle one).

42. . If a light ray travels from a more optically dense substance to a less optically dense substance, the light ray will (bend toward the normal/bend away from the normal) (circle one).

43. What is the ability of waves to spread around or through a barrier is called __DIFFRACTION____. (reflection, refraction, or diffraction) CHARGE and ELECTRICTY

44. What is an electrical conductors? EASILY REMOVED ELECTRONS (METALS) 45. What is an electrical insulator? TIGHTLY BOUND ELECTRONS (PLASTICS OR RUBBER) 46. If a suspended object is attracted to another object which has a charge, what can you conclude? (2 things) OPPOSITE OR DIFFERENT (CHARGED AND UNCHARGED)

47. How does the electric force between two charges change when the distance between them is doubled? (does it increase or decrease) _____DECREASE_____

48. What is the charge of a proton? _____POSITIVE____ where is it located? ______NUCLEUS______49. What is the charge of a neutron? ______NONE___ where is it located? ______NUCLEUS___ 50. What is the charge of an electron? ___NEGATIVE____ where is it located? _____ORBITAL__

51. If an ion of Ca has a +2 charge, does it have more protons or electrons? __PROTONS____ 52. Can you gain or lose protons? __NO____ Can you gain or lose electrons? __YES___

53. The rate of flow of electric charge, is the ______CURRENT, I__.

54. The amount of charge that passes through a certain light bulb in 4.00 s is 5.75 C. Determine the current in the light bulb. 1.44 A

55. Resistance is defined as ______REDUCING THE FLOW OF ELECTRICITY_____. 56. If the length of the wire is doubled, will the amount of resistance increase or decrease? ___DECREASE_ 57. If the diameter of a wire is doubled, will the amount of resistance increase or decrease? __INCREASE

58. An ammeter registers 2.5 A of current in a wire that is connected to a 9.0 V battery. What is the wire’s resistance? 3.6 OHMS

59. An electric heater is operated by applying a potential difference of 50.0 V across a nichrome wire of total resistance 8.00 Ω. What is the power rating of the heater? 313W

60. Fill in the blanks in the chart. DEVICE P R I ∆V

Computer 214W 95 Ω 1.5 A 143 V

Portable Stereo 15.0 W 0.42 Ω 6A 2.5 V

Coffee Maker 500.0 W 14 Ω 6.0 A 83 V

Graphing Calculator 0.13W 200 Ω 25.2 mA 5.0 V

61. If the battery supplies 8.0V and the device has a resistance of 4.0, what does the ammeter read? The voltmeter? What is the direction of conventional current? 2A 8 V COUNTER-CLOCKWISE

62. What is the equivalent resistance of a series circuit with resistors of 7 Ω, 13 Ω, and 20Ω?

40 Ω

63. What is the equivalent resistance of a parallel circuit with resistors of 7 Ω, 13 Ω, and 20Ω?

3.7 Ω

64. If you add more resistors in series, does your total resistance increase or decrease?_____INCREASE__ So, does your current drawn from the battery increase or decrease? ___DECREASE___

65. If you add more resistors in parallel, does your total resistance increase or decrease?__DECREASE_ So, does your current drawn from the battery increase or decrease? _____INCREASE____

66. What is DC? ____DIRECT CURRENT_ What is AC? ALTERNATING CURRENT

MAGNETS 67. When allowed to float freely, the North pole of a bar magnet points Geographic __NORTH_____ toward a region in Canada because it is attracted to magnetic __SOUTH___.

68. The force experienced when the N-poles of two magnets are brought close together is what type of force? (attractive or repulsive) ______REPULSIVE______

69. What is the shape of a magnetic field surrounding a current- carrying wire? __CIRCULAR__

70. Describe 3 methods to de-magnetize a magnet, at least partially? ______HEAT______, ______HIT______, or _____DROP______71. If a bar magnet is broken into two pieces, how many poles does each magnet have? ___2__ 72. Is the magnetic field surrounding a current carrying wire strongest closest to the poles, or far from the poles? ______CLOSEST______

73. In the diagram below, the magnet labeled as #2 would have its N – pole facing what direction? UP

74. What device converts electrical energy into mechanical energy? __MOTOR______

75. What device converts mechanical energy into electrical energy? ______GENERATOR_____

76. What device uses two coil wrapped round an iron core to change the voltage across a circuit? ______TRANSFORMER______

77. What process involves inducing voltage and current by changing the magnetic field around a conductor? ____ELECTROMAGNETIC INDUCTION______

78. The primary coil of a transformer has 500 turns and is connected to a 75V source. What number of turns in the secondary will produce 150V? 1000 TURNS

 Is this a step-up or step-down transformer? ___STEP-UP TRANSFORMER_