6th Grade Chapter 19 Test

6th Grade Chapter 19 Test
Modified True/False
Indicate whether the statement is true or false. If false, change the identified word or phrase to make the statement true.
____ 1. The positive electrode in a dry-cell battery is a zinc rod. _________________________
____ 2. In a battery, chemical energy is transformed into electrical energy. _________________________
____ 3. Charging by contact occurs when an electric field rearranges the charges in an object. _________________________
____ 4. Unlike magnetic poles repel each other. _________________________
____ 5. The amount of positive charge on a proton equals the amount of negative charge on a neutron. _________________________
____ 6. As the amount of charge on either of two charged objects increases, the electric force between the objects decreases. _________________________
____ 7. An electromagnet is a current-carrying wire wrapped around a copper core. _________________________
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____ 8. Which of these particles can be found in the nucleus of an atom?
a.
electrons
b.
electrons and protons
c.
electrons, protons, and neutrons
d.
neutrons and protons
____ 9. Why do we say that atoms are neutral?
a.
They contain neutrons.
b.
They make up all matter.
c.
They have zero total charge.
d.
They remain motionless.
____ 10. Which of the following does NOT affect the electric force between objects?
a.
the amount of charge on the objects
b.
the distance between the objects
c.
the size of the objects
d.
whether the objects have like or unlike charges
____ 11. Why are electrically charged objects able to exert force on one another without touching?
a.
They are affected by gravity.
b.
They are surrounded by a magnetic field.
c.
They are surrounded by an electric field.
d.
They create a current.
____ 12. What happens to an object when it picks up excess electrons by contact?
a.
It becomes an insulator.
b.
It becomes negatively charged.
c.
It becomes positively charged.
d.
It gives off a bright spark.
____ 13. Which word describes material in which electric charges move easily?
a.
conductor
b.
field
c.
insulator
d.
magnet
____ 14. Why does a wire remain electrically neutral?
a.
because electrons flow in and out at the same rate
b.
because it has more protons than electrons
c.
because it is coated in neutrons
d.
because it stays charged by flowing electrons
____ 15. Cary and Alana are making an electromagnet for a class project. To make the electromagnet, they wrap a current-carrying wire around an iron core. What is the relationship between electricity and magnetism that makes it possible for them to create an electromagnet?
a.
A moving electric charge is surrounded by a magnetic field.
b.
Magnets are electrically charged objects.
c.
The wire conductor is made of magnetic material.
d.
All circuits are temporary magnets.
____ 16. Ricardo is studying different changes in electric circuits. What happens when he increases the voltage in a circuit?
a.
The circuit breaks.
b.
The current increases.
c.
The flow of electrons slows down.
d.
The resistance increases.
____ 17. Which device converts mechanical energy into electrical energy by rotating a wire loop inside a magnetic field?
a.
a battery
b.
a series circuit
c.
an electric generator
d.
an electromagnet
____ 18. Rita is writing a report that compares magnets and electric charges. Which of these is NOT a characteristic shared by magnets and electric charges?
a.
Their forces are stronger as they move closer together.
b.
Their like charges repel and unlike charges attract.
c.
They are surrounded by fields that exert force at a distance.
d.
They have charges arranged in domains.
____ 19. Kendra and Jamal are looking at this diagram in a science book. The diagram shows the magnetic domains of the same object before and after it is acted on by the force of a permanent magnet.

What type of object does this diagram show?
a.
a bar magnet
b.
a compass
c.
an electromagnet
d.
a temporary magnet
____ 20. Which of the following transforms mechanical energy to electric energy?
a.
a lightning rod
b.
an electromagnet
c.
an electric generator
d.
a parallel circuit
____ 21. A material through which electrons can move easily is a _____.
a.
conductor
c.
insulator
b.
electromagnet
d.
nucleus
____ 22. Each of the following is an example of an insulator except _____.
a.
copper
c.
rubber
b.
glass
d.
wood
____ 23. An atom has equal numbers of protons and _____.
a.
electrons
c.
ohms
b.
neutrons
d.
volts
____ 24. The process of providing a path to drain excess charge into Earth is called _____.
a.
electromagnetic induction
c.
lightning
b.
grounding
d.
resistance
____ 25. Which of the following correctly states Ohm's Law?
a.
resistance = voltage + current
c.
voltage = current / resistance
b.
resistance = voltage x current
d.
voltage = current x resistance
____ 26. An object with equal amounts of positive and negative charge is electrically _____.
a.
charged
c.
neutral
b.
negative
d.
positive
____ 27. If the distance between two charged objects increases, the electric force between them _____.
a.
decreases
c.
remains the same
b.
increases
d.
stops
____ 28. Every proton and electron is surrounded by a(n) _____.
a.
electric circuit
c.
insulator
b.
electric field
d.
magnetic pole
____ 29. Which of the following is an example of charging by induction?
a.
clothes sticking together after tumbling in a dryer
b.
making a paper clip into a temporary magnet
c.
rubbing a balloon against a person's hair
d.
sticking a balloon to a wall after rubbing it on a sweater
____ 30. When an object has more negative charge than positive charge, the result is called a _____.
a.
electric discharge
c.
series circuit
b.
magnetic domain
d.
static charge
____ 31. The SI unit for electric current is the _____.
a.
ampere
c.
ohm
b.
electron
d.
volt

____ 32. In the figure shown, the shock that a person gets when touching a metal doorknob after walking across a carpet is caused by _____.
a.
charging by contact
c.
electromagnetic induction
b.
charging by induction
d.
Ohm's Law
____ 33. In the figure shown the spark that jumps between the hand and the doorknob is an example of _____.
a.
a chemical reaction
c.
electromagnetism
b.
an electric discharge
d.
grounding
____ 34. In the figure shown, the spark that occurs results from the movement of _____.
a.
atoms
c.
neutrons
b.
electrons
d.
protons
____ 35. Electrical energy is converted into heat and light in a _____.
a.
battery
c.
magnetic pole
b.
filament
d.
voltmeter
____ 36. Wet-cell batteries are typically used to supply electrical energy to _____.
a.
automobiles
c.
flashlights
b.
calculators
d.
portable CD players
____ 37. One difference between dry-cell batteries and wet-cell batteries is that _____.
a.
Dry-cell batteries are not rechargeable.
b.
No chemical reactions occur in dry-cell batteries.
c.
No chemical reactions occur in wet-cell batteries.
d.
Wet-cell batteries do not have an electrolyte.
____ 38. Which of the following is true about the magnetic field lines of a bar magnet?
a.
They are closest together at the magnet's poles.
b.
They are closest together near the magnet's center.
c.
They are closest together where the magnetic field is weakest.
d.
They extend in a straight line from the magnet's center.
____ 39. Each of the following elements is magnetic except _____.
a.
aluminum
c.
iron
b.
cobalt
d.
nickel
____ 40. The magnetic fields of all the atoms in a magnetic domain _____.
a.
add together
c.
cause a chemical reaction
b.
cancel each other out
d.
produce an electric current

____ 41. In the figure shown, what must happen for current to flow?
a.
A chemical reaction must occur.
c.
The wire loop must be heated.
b.
The magnet's poles must be reversed.
d.
The wire loop must rotate.
____ 42. The generator in the figure shown converts _____.
a.
chemical energy to electrical energy
b.
electrical energy to chemical energy
c.
electrical energy to mechanical energy
d.
mechanical energy to electrical energy
____ 43. Which of the following occurs in a hydroelectric power plant?
a.
Electrical energy is used to move water.
b.
Kinetic energy is converted into electrical energy.
c.
Kinetic energy causes a chemical reaction that produces steam.
d.
Hot water causes a chemical reaction that generates electrical energy.
____ 44. The unit used for measuring electric resistance is the _____.
a.
ampere
c.
ohm
b.
degree
d.
volt
____ 45. A circuit that has more than one closed path for current to follow is referred to as a(n) _____.
a.
electron circuit
c.
parallel circuit
b.
magnetic circuit
d.
series circuit
____ 46. Lightning is an example of _____.
a.
charging by contact
c.
electric discharge
b.
circuit electricity
d.
electromagnetic induction
____ 47. The chemical reactions that occur within a battery cell are caused by chemicals in the _____.
a.
electrolyte
c.
negative electrode
b.
magnetic poles
d.
positive electrode
____ 48. If the current in a portable radio is 0.4 amperes, and the resistance of the circuit is 30.0 ohms, what is the voltage provided by the radio's battery?
a.
0.01 volts
c.
30.4 volts
b.
12 volts
d.
75 volts
____ 49. Which of the following statements about the forces between charged objects is not true?
a.
As the distance between charged objects decreases, the electric force between them decreases.
b.
If one object is positively charged and another is negatively charged, the objects will attract each other.
c.
Two negatively charged objects will repel each other.
d.
Two positively charged objects will repel each other.
____ 50. To make electric charges flow in a circuit, there must be a(n) _____.
a.
electric field
c.
insulator
b.
electrolyte
d.
magnetic domain

____ 51. In the figure shown, how much current flows in circuit 2?
a.
0.15 amperes
c.
40 amperes
b.
6.67 amperes
d.
60 amperes
____ 52. In the figure shown, what is the resistance of circuit 4?
a.
0.025 ohms
c.
12 ohms
b.
6.4 ohms
d.
40 ohms
____ 53. In the figure shown, which circuits have the same resistance?
a.
circuits 1 and 2
c.
circuits 2 and 4
b.
circuits 1 and 3
d.
circuits 3 and 4

____ 54. In the figure shown, diagram B illustrates _____.
a.
a parallel circuit
c.
grounding
b.
a series circuit
d.
resistance
____ 55. In the figure shown, if Lamp 1 burns out, what will happen?
a.
Lamp 2 in both diagrams will go out.
b.
Lamp 2 in diagram A will blink on and off.
c.
Lamp 2 only in diagram A will go out.
d.
Lamp 2 only in diagram B will go out.
____ 56. Homes are wired as shown in which diagram in this figure?
a.
diagram A
c.
either diagram A or B
b.
diagram B
d.
neither diagram A nor B

____ 57. In the figure show, what happens when the amount of current flowing in the wire coil is increased?
a.
The magnetic field becomes stronger.
b.
The magnetic field disappears.
c.
The position of the north and south poles is reversed.
d.
The strength of the magnetic field decreases.
____ 58. In the figure shown, what would happen if the direction of current flow in the wire coil were reversed?
a.
The electromagnet would no longer work.
b.
The north and south poles would switch places.
c.
The strength of the magnetic field would increase.
d.
The strength of the magnetic field would decrease.

____ 59. In the figure shown, how does the bar magnet turn the paper clip into a temporary magnet?
a.
magnetic domains of the paper clip to point in different directions
b.
by causing the magnetic domains of the paper clip to point in one direction
c.
by generating an electric current in the paper clip
d.
by producing a chemical change in the paper clip
____ 60. In the figure shown, what would happen if the bar magnet's south pole were used instead of its north pole?
a.
The magnet would be able to attract the paper clip, but not the screw.
b.
The magnet would be able to attract the screw, but not the paper clip.
c.
The paper clip would no longer be able to attract the screw.
d.
The paper clip would still be able to attract the screw.
____ 61. The energy conversion in an electric generator is
a.
mechanical to electric.
c.
chemical to electric.
b.
electrical to mechanic.
d.
electrical to chemic.
____ 62. A stationary charged particle is surrounded by a(n)
a.
electric field.
c.
electric field and a magnetic field.
b.
magnetic field.
d.
electric current.
____ 63. If the resistance in a circuit is doubled while the voltage remains constant, the current
a.
is doubled.
b.
remains constant.
c.
is halved.
d.
cannot be determined from the information provided.
____ 64. The sparks that occur when you pull a wool sweater over your hair is an example of an electric
a.
field.
c.
current.
b.
discharge.
d.
resistance.
____ 65. Which of the following is an electric conductor?
a.
wood
c.
glass
b.
gold
d.
rubber
____ 66. All of the following apply to an electric current, EXCEPT:
a.
it is surrounded by an magnetic field.
b.
it transfers electric energy.
c.
it is measured in volts.
d.
it is a flow of electrons.
____ 67. An electromagnet is a type of
a.
permanent magnet.
c.
generator.
b.
temporary magnet.
d.
parallel circuit.
____ 68. Ohm's law expresses the relationship of
a.
series and parallel circuits.
b.
voltage, current, and electric discharge.
c.
electric charge and magnetic field.
d.
voltage, current, and resistance.
____ 69. In a parallel circuit, the electrons
a.
all follow the same path.
c.
do not carry an electric current.
b.
can follow more than one path.
d.
have a static charge.
____ 70. A copper wire is an example of a(n)
a.
electric circuit.
c.
insulator.
b.
magnetic material.
d.
conductor.
____ 71. The path in which electrons flow is an electric
a.
current.
c.
insulator.
b.
circuit.
d.
field.
____ 72. A group of iron atoms whose magnetic poles are oriented in the same direction are a(n)
a.
electromagnet.
c.
magnetic domain.
b.
magnetic field.
d.
magnetic pole
Completion
Complete each statement.

73. In the figure shown, air currents have caused the bottom of the storm cloud to become ____________________ charged.
74. In the figure shown, charging by ____________________ has caused the ground to become positively charged.
75. In the figure shown, lightning occurs when the ____________________ between the cloud and the ground causes charges to move.

76. In the figure shown, electric current will flow only if the switch is ____________________.
77. In the figure shown, if the switch is closed and one wire is disconnected, the lightbulb will ____________________.
78. In the figure shown, closing the switch in this circuit causes an ____________________ to travel through the circuit, which makes electrons in the bulb start to flow and the bulb to light.
Unscramble the word in italics to complete these sentences.
79. A material in which electrons do not flow easily is a(n) luntsiora. ____________________
80. A lllepaar circuit is one that provides more than one path for electrons. ____________________
81. A wire in which a current flows wrapped around an iron core produces a(n) cogenateeltrm. ____________________
82. gelotva is a measure of how much electrical energy an electron carries. ____________________
83. A circuit that provides only one path for electrons is a eeriss circuit. ____________________
84. A nuccdotro is a material in which electrons flow easily. ____________________
Choose the italicized word that correctly completes the sentence.
85. The closed path in which electric charges can flow is an electric ____________________ circuit / current.
86. Electrons flow from the ____________________ positive / negative terminal of a battery.
87. Collisions of electrons with other particles in a circuit convert electrical ____________________ energy / charge into heat or light.
88. V = IR is the equation that expresses the relationship known as ____________________ Ohm's / Ampere's law.
89. In the formula V = IR, current is represented by the letter ____________________ I / R.
90. A light switch is part of a ____________________ series / parallel circuit if it controls all of the lights at once.
91. As the distance between two electric charges decreases, the electric force between them ____________________ increases / decreases.
92. The electric force that one electron exerts on another electron is always ____________________ attractive / repulsive.
93. The electric field around an electron points ____________________ toward / away from the electron.
94. The magnetic field around a bar magnetic is ____________________ strongest / weakest at the magnetic poles.
95. Materials such as iron are magnetic materials because they contain magnetic ____________________ currents / domains.
96. The voltage between two points in a circuit ____________________ increases / decreases when the electric field in the circuit increases.
97. In the equation V = IR, the letter “I” represents ____________________, which is measured in units of ____________________.
98. Collisions between moving electrons in a circuit and other particles, such as atoms, result in ____________________.
99. A permanent magnet is formed when all of the ____________________ of a magnetic material line up.
100. A(n) ____________________ converts mechanical energy into electric energy using the relative motion of a magnet and a wire loop.
101. A compass needle points north because the Earth is surrounded by a(n) ____________________.
Matching
Match each term with the correct definition.
a.
insulator
f.
voltage
b.
conductor
g.
magnetic domain
c.
static charge
h.
electromagnetic induction
d.
electric discharge
i.
electric circuit
e.
electric resistance
j.
electric current
____ 102. flow of electric charges
____ 103. imbalance of electric charge on an object
____ 104. group of atoms that have their magnetic poles pointing in the same direction
____ 105. material that allows electric charges to move easily
____ 106. production of electric current through the movement of a magnet and a loop
____ 107. material that does not allow electric charges to move easily
____ 108. measure of how difficult it is for electrons to flow
____ 109. measure of the amount of electrical energy transferred by an electric charge
____ 110. closed path in which electric charges flow
____ 111. movement of static charge from one place to another
Match each item with the correct description below.
a.
charging by contact
f.
electric resistance
b.
charging by polarization
g.
electromagnetic induction
c.
electric discharge
h.
static charge
d.
electric current
i.
magnetic domain
e.
electric circuit
____ 112. an imbalance of electric charge on an object
____ 113. transfer of electric charge between two objects that are touching one another
____ 114. production of an electric current by moving a wire loop and a magnet relative to each other
____ 115. the flow of electrons in a circuit
____ 116. transfer of electric charge between two objects that are not touching one another
____ 117. a group of atoms that have their magnetic poles pointing in one direction
____ 118. a closed path in which electric charges can flow
____ 119. rearrangement of electric charges in an object in an electric field
____ 120. a measure of how difficult it is for electrons to flow in an object
Short Answer
121.
Susan drew this diagram on the chalkboard in class.

What do the arrows in this simple electric circuit represent?
122.
How does the balance of protons and electrons determine whether an atom is electrically charged?
123.
Why is copper commonly used to make electric wires?
124.
How can you use the “30-30 rule” to protect yourself during a thunderstorm?
125.
How does connecting a battery to a circuit make charges flow?
126.
What is the function of a voltmeter?
127.
How does the electrolyte determine whether a battery is a wet-cell or a dry-cell?
128.
In what way are electric fields and magnetic fields similar?
129. What happens to the total charge on a wire when a current flows through the wire?
130. In a series circuit with a constant voltage, what is the effect on current if the number of lightbulbs in the circuit is doubled?
131. How can a broken wire affect a series circuit differently than a parallel circuit?
132. Make a general statement about the relationship between electricity and magnetism. Then, identify two facts that support your statement.
133. How are a battery and an electric generator similar and how are they different?
134. How can you determine whether the bulbs in a string of holiday lights are part of a series circuit or part of a parallel circuit?
135. Use the information in the table to match the descriptions to the materials.

Electrical Conductor
Attracted to a Magnet
Material A
yes
yes
Material B
yes
no
Material C
no
no
a. iron nail
b. copper wire
c. glass rod
Study the diagram and use it to answer the questions.

136. What is this a diagram of?
137. What is the source of energy in the diagram?
138. What would be the effect on lightbulb A if the switch were closed?
139. What would be the effect on lightbulb B if the switch were opened?
Essay
140.
What is electric resistance? How is it responsible for creating the light in a lightbulb? Be sure to explain what transformations of energy take place as electrons move through a circuit.
141. Describe how your day at school would be different if there were no electric power.