Download Second Semester Review - Parkway C-2

Name_____________________________________________________
Date___________________ Block_______
Second Semester Review
True/False
Indicate whether the statement is true or false.
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1. Mechanical advantage is always greater than 1.
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2. According to the conservation of mechanical energy, the kinetic energy before plus the kinetic energy after
equals the potential energy before plus the potential energy after.
____
3. The entropy of a system measures the state of disorder of the system.
____
4. Mechanical energy can be converted to thermal energy through friction, but the reverse never occurs.
____
5. Some machines can accomplish work with no increase in entropy because they have no friction associated
with them.
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6. The speed of a wave depends on the medium through which it travels and the amount of energy it carries.
____
7. The incident angle is the angle formed between a barrier and the direction of wave propagation.
____
8. Because of the Doppler effect, an observer will hear a sound moving away from her as being higher in pitch.
____
9. Sound travels faster on a cold day than on a warm day.
____ 10. A string clamped at both ends can resonate at any half-wavelength interval.
____ 11. The speed of light measured by an observer moving toward the source of light is greater than that measured
by a stationary observer.
____ 12. A convex mirror forms a virtual, diminished, and upright image for all real objects regardless of the location
of the object.
____ 13. A concave mirror of focal length 10 cm forms an upright and diminished image of a real object placed at a
distance of 5 cm from the mirror.
____ 14. The normal with regard to reflection is perpendicular to the surface of a plane mirror.
____ 15. The two types of charges, positive and negative, are not created alone, but in pairs.
____ 16. Two objects with the same type of charge attract each other.
____ 17. Electric charge is neither created nor destroyed; it is conserved.
____ 18. Electric potential difference is the change in kinetic energy per unit charge in an electric field.
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A
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____ 19. Which type of energy is associated with a body’s height above the ground?
a. thermal energy
c. gravitational potential energy
b. elastic potential energy
d. rest energy
____ 20. Which is the transfer of thermal energy through direct contact of particles?
a. conduction
c. convection
b. radiation
d. specific heat
____ 21. Which is the transfer of thermal energy through the motion of particles caused by temperature differences?
a. conduction
c. convection
b. radiation
d. specific heat
____ 22. Which is not associated with an increase in entropy?
a. spontaneous processes
c. an increase in thermal energy
b. an inefficient engine
d. a more orderly arrangement of particles
____ 23. Which scenario would result in a drop in the pitch being observed?
a. The observer moves closer to a stationary source.
b. The source moves toward a stationary observer.
c. A source moving toward an observer suddenly stops.
d. The observer and the source move in the same direction at the same speed.
____ 24. Which describes a sound wave?
a. A sound wave travels in a vacuum.
b. A sound wave is a longitudinal wave.
c. A sound wave is an electromagnetic wave.
d. A sound wave has one constant speed.
____ 25. Which term describes a material that does not allow light to be transmitted?
a. translucent
c. polarized
b. transparent
d. opaque
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____ 26. Which of the following ray diagrams is correct?
a.
c.
b.
d.
____ 27. What is the nature of an image formed by a concave mirror of focal length 10 cm for a real object placed 3
cm from the mirror?
a. Real and inverted
c. Virtual and inverted
b. Real and upright
d. Virtual and upright
____ 28. Which is formed by divergent rays?
a. virtual image
b. real image
c.
d.
focal point
object
____ 29. Which is formed by convergent rays?
a. virtual image
b. real image
c.
d.
focal point
object
____ 30. Where do incident rays that are parallel to the principal axis converge to after reflecting off a concave
mirror?
a. a virtual image
c. a focal point
b. a real image
d. They don’t converge.
____ 31. In Young’s double-slit experiment using monochromatic light, the interference pattern consists of a central
_____.
a. Dark band with multi-colored bands on either side.
b. Bright band with alternate dark and bright bands on either side.
c. Dark band with alternate bright and dark bands on either side.
d. White band with multi-colored bands on either side.
____ 32. A negatively charged balloon sticks to a wooden door. However, an uncharged balloon does not stick to a
wooden door. What is the nature of the charge on the wooden door?
a. Electrically neutral
c. Conductor
b. Positively charged
d. Lacking protons
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____ 33. What change is observed in the strength of an electric field around a charged object if the magnitude of the
test charge is doubled?
a. Electric field is doubled.
b. Electric field is halved.
c. Electric field remains unchanged.
d. Electric field reduces to one-fourth of the original value.
____ 34. _____ are not valid units for the measurement of electric potential difference.
a. V
c. N m/C
b. J/C
d. C/J
____ 35. How much energy does it require to move a constant positive charge of 2 C through a potential difference of
3 V?
a. 6 J
c. 1.5 J
b. 0 J
d. 3 J
____ 36. The direction of the force on a positive test charge near another positive charge is _____ the other charge.
a. away from
c. parallel to
b. toward
d. perpendicular
____ 37. A __________ is described as a device with specific resistance and is used to control current.
a. battery
c. parallel connection
b. resistor
d. series connection
____ 38. A lamp draws a current of 0.50 A when it is connected to a 120 V source? What is the resistance of the
lamp?
c. 2.4 102 ohms
a. 4.17 10-2 ohms
b. 60 ohms
d. 24 102 ohms
____ 39. A/An _____ is described as the flow of positive charges that move from a higher to lower potential energy.
a. electron flow
c. electric circuit
b. conventional current
d. conventional circuit
____ 40. A/An _____ is a type of electric circuit in which there are multiple paths, whereas a/an _____ is a type of
electric circuit in which there is a single current path.
a. parallel connection, series connection
c. conductor, insulator
b. series connection, parallel connection
d. insulator, conductor
____ 41. A/An _____ is described as the flow of charged particles.
a. electric field
c. electric current
b. electric potential difference
d. gravitational force
____ 42. A/An _____ is described as the flow of electric charge or current equal to one coulomb per second.
a. volt
c. capacitance
b. capacitor
d. ampere
____ 43. If a resistor is added to a series circuit, the equivalent resistance:
a. increases
c. remains the same
b. decreases
d. becomes zero
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____ 44. The number of current paths in a series circuit is:
a. one
c.
b. two
d.
three
four
____ 45. A 20.0-Ω resistor and a 40.0-Ω resistor are connected in series across a battery. If the current is 2.00 A, what
is the voltage of the battery?
a. 30.0 V
c. 80.0 V
b. 60.0 V
d. 1.20 × 102 V
____ 46. A 2.00-Ω resistor and a 12.0-Ω resistor are connected in parallel across a 20.0-V battery. What is the current
flowing through the 2.00-Ω resistor?
a. 1.67 A
c. 11.6 A
b. 1.40 A
d. 10.0 A
Short Answer
47. What are the two equivalent expressions of the efficiency of a machine?
48. What is the mechanical advantage of any machine?
49. In a tug-of-war, each side pulls with a force of 500 newtons, but the rope does not move. How much work is
done?
50. State the law of conservation of energy.
51. If a driver suddenly slams on the brakes of her car and skids to a halt, where does the car’s kinetic energy go?
52. A red apple is illuminated by green light. What color would the apple appear?
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53. The electric field around a positive charge is shown in the diagram. Describe the nature of these lines.
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54. Electric field lines around two charges are shown in the diagram. Identify the type of charges on the objects
X and Y.
Problem -- Show your work for full credit.
55. A 6110-kg bus traveling at 20.0 m/s can be stopped in 24.0 s by gently applying the brakes. If the driver
slams on the brakes, the bus stops in 3.90 s. What is the average force exerted on the bus in both these stops?
56. Candona strikes a 0.055-kg golf ball with a force of 260 N. If the ball moves with a velocity of 65 m/s,
calculate the time the ball is in contact with the club.
57. A force of 200 N acts on a 7.20-kg bowling ball for 0.350 s. Calculate its change in velocity.
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58. Two identical 2200 kg cars, traveling at 11 m/s, collide head-on and stop.
a) What is the change in momentum for each car?
b) What is the change in kinetic energy for each car?
59. A student lifts a 1.2-kg bag from her desk, which is 0.59-m high, to a locker that is 2.9-m high. What is the
gravitational potential energy of the bag relative to the desk?
60. What is the force between two small charged spheres that have charges of 2 × 10–7 C and 3 × 10–7 C and are
placed 30 cm apart in air?
61. A positive test charge of 6.00 µC is placed in an electric field, which exerts a force of 5.00 × 10–4 N on the
test charge. What is the magnitude of the electric field strength at the location of the test charge?
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ID: A
Second Semester Review
Answer Section
TRUE/FALSE
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
F
F
T
F
F
F
F
F
F
T
F
T
F
T
T
F
T
F
MULTIPLE CHOICE
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
C
A
C
D
C
B
D
D
D
A
B
C
B
A
C
D
A
A
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ID: A
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.
B
C
B
A
C
D
A
A
D
D
SHORT ANSWER
47. Efficiency, e, equals either work output/work input times 100 or mechanical advantage/ideal mechanical
advantage times 100.
48. Mechanical advantage is equal to the resistance force divided by the effort force.
49. No work is done, because displacement is zero.
50. In a closed, isolated system, energy can neither be created nor destroyed.
51. The kinetic energy is transformed into heating the wheels, tires, and road.
52. The apple would appear black because a red apple can only reflect red light. The green light is absorbed by
the apple and no light is reflected back to the observer.
53. The electric lines always point away from a positive charge. The lines never cross each other. In addition,
electric lines always leave the positive charge and enter a negative charge.
54. The charge on X is positive and that on Y is negative.
PROBLEM
55. F gentle braking = 5.09 × 103 N
F hard braking = 3.13 × 104 N
56. 0.014 s
57. 9.72 m/s
58. a) For each car, loss of momentum is 2.4
reference frame.
104 kg m/s, one positive and the other negative, depending on the
b) For each car, loss of kinetic energy is 1.3
59. 27 J
60. 6 × 10–3 N
61. 83.3 N/C
10-5 J. Kinetic energy is always positive.
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