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93 Cards in this Set
- Front
- Back
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Materials in which the electrons are bound very loosely to the nuclei and can move about
freely within the material are referred to as A) insulators. B) conductors. C) semiconductors. D) superconductors. |
conductors
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A negatively charged rod is brought near one end of an uncharged metal bar. The end of the
metal bar farthest from the charged rod will be charged A) positive. B) negative. C) neutral. D) none of the given answers |
negative
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Sphere A carries a net positive charge, and sphere B is neutral. They are placed near each
other on an insulated table. Sphere B is briefly touched with a wire that is grounded. Which statement is correct? A) Sphere B remains neutral. B) Sphere B is now positively charged. C) Sphere B is now negatively charged, D) The charge on sphere B cannot be determined without additional information |
sphere B is now negatively charged
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A point charge of +Q is placed at the center of a square. When a second point charge of -Q
is placed at one of the square's corners, it is observed that an electrostatic force of 2.0 N acts on the positive charge at the square's center. Now, identical charges of -Q are placed at the other three corners of the square. What is the magnitude of the net electrostatic force acting on the positive charge at the center of the square? A) zero B) 2.8 N C) 4.0 N D) 8.0 N |
zero
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The absolute potential at a distance of 2.0 m from a positive point charge is 100 V. What
is the absolute potential 4.0 m away from the same point charge? A) 25 V B) 50 V C) 200 V D) 400 V |
50 V
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For a proton moving in the direction of the electric field
A) its potential energy increases and its electric potential decreases. B) its potential energy decreases and its electric potential increases. C) its potential energy increases and its electric potential increases. D) its potential energy decreases and its electric potential decreases. |
its potential energy decreases and its electric potential decreases.
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The electron-volt is a unit of
A) voltage. B) current. C) power. D) energy. |
energy
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A 110-V hair dryer is rated at 1200 W. What current will it draw?
A) 0.090 A B) 1.0 A C) 11 A D) 12 A |
11 A
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Is it possible for two negative charges to attract each other?
A) Yes, they always attract. B) Yes, they will attract if they are close enough. C) Yes, they will attract if one carries a larger charge than the other. D) No, they will never attract. |
No, they will never attract
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A surface on which all points are at the same potential is referred to as
A) a constant electric force surface. B) a constant electric field surface. C) an equipotential surface. D) an equivoltage surface. |
an equipotential surface
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A negative charge is moved from point A to point B along an equipotential surface.
A) The negative charge performs work in moving from point A to point B. B) Work is required to move the negative charge from point A to point B. C) Work is both required and performed in moving the negative charge from point A to point B. D) No work is required to move the negative charge from point A to point B |
No work is required to move the negative charge from point A to point B
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At twice the distance from a point charge, the strength of the electric field
A) is four times its original value. B) is twice its original value. C) is one-half its original value. D) is one-fourth its original value. |
is one-fourth its original value
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Electric field lines near positive point charges
A) circle clockwise. B) circle counter-clockwise. C) radiate inward. D) radiate outward. |
radiates outward
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Two point charges, separated by 1.5 cm, have charge values of 2.0 and -4.0 μC,
respectively. What is the magnitude of the electric force between them? A) 400 N B) 360 N C) 320 N D) 160 N |
320 N
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Three identical point charges of 2.0 μC are placed on the x-axis. The first charge is at the
origin, the second to the right at x = 50 cm, and the third is at the 100 cm mark. What are the magnitude and direction of the electrostatic force which acts on the charge at the origin? A) 0.18 N left B) 0.18 N right C) 0.36 N left D) 0.36 N right |
0.18 N left
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A current that is sinusoidal with respect to time is referred to as
A) a direct current. B) an alternating current. |
an alternating current
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What potential difference is required to cause 4.00 A to flow through a resistance of 330
Ω? A) 12.1 V B) 82.5 V C) 334 V D) 1320 V |
1320 V
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What is the resistance of a circular rod 1.0 cm in diameter and 45 m long, if the resistivity
is 1.4 × 10-8 Ω∙m? A) 0.0063 Ω B) 0.0080 Ω C) 0.80 Ω D) 6.3 Ω |
0.0080 Ω
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A lamp uses a 150-W bulb. If it is used at 120 V, what current does it draw?
A) 0.800 A B) 1.25 A C) 150 A D) 8 kA |
1.25 A
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How much energy does a 100-W light bulb use in 8.0 hours?
A) 0.0080 kWh B) 0.80 kWh C) 13 kWh D) 800 kWh |
0.80 kWh
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Two parallel-plate capacitors are identical in every respect except that one has twice the
plate area of the other. If the smaller capacitor has capacitance C, the larger one has capacitance A) C/2. B) C. C) 2C. D) 4C. |
2C
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A dielectric material such as paper is placed between the plates of a capacitor. What
happens to the capacitance? A) no change B) becomes larger C) becomes smaller D) becomes infinite |
becomes larger
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A dielectric material such as paper is placed between the plates of a capacitor holding a
fixed charge. What happens to the electric field between the plates? A) no change B) becomes stronger C) becomes weaker D) reduces to zero |
becomes weaker
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A parallel-plate capacitor is filled with air, and the plates are separated by 0.050 mm. If
the capacitance is 17.3 pF, what is the plate area? A) 4.9 × 19-5 m2 B) 9.8 × 10-5 m2 C) 2.4 × 10-4 m2 D) 4.8 × 10-4 m2 |
9.8 × 10-5 m2
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20 V is placed across a 15 μF capacitor. What is the energy stored in the capacitor?
A) 150 μJ B) 300 μJ C) 3.0 mJ D) 6.0 mJ |
3.0 mJ
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The length of a wire is doubled and the radius is doubled. By what factor does the
resistance change? A) four times as large B) twice as large C) half as large D) quarter as large |
half as large
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When resistors are connected in series,
A) the same power is dissipated in each one. B) the potential difference across each is the same. C) the current flowing in each is the same. D) More than one of the given answers is true. |
the current flowing in each is the same
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Three identical resistors are connected in series to a battery. If the current of 12 A flows from the battery,
how much current flows through any one of the resistors? A) 12 A B) 4 A C) 36 A D) zero |
12 A
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Three identical resistors are connected in series to a 12-V battery. What is the voltage across any one of
the resistors? A) 36 V B) 12 V C) 4 V D) zero |
4 V
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As more resistors are added in series to a constant voltage source, the power supplied by the source
A) increases. B) decreases. C) does not change. D) increases for a time and then starts to decrease. |
decreases
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When resistors are connected in parallel, we can be certain that
A) the same current flows in each one. B) the potential difference across each is the same. C) the power dissipated in each is the same. D) their equivalent resistance is greater than the resistance of any one of the individual resistances. |
the potential difference across each is the same
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Three identical resistors are connected in parallel to a 12-V battery. What is the voltage of any one of the
resistors? A) 36 V B) 12 V C) 4 V D) zero |
12 V
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Three identical resistors are connected in parallel to a battery. If the current of 12 A flows from the
battery, how much current flows through any one of the resistors? A) 12 A B) 4 A C) 36 A D) zero |
4 A
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As more resistors are added in parallel to a constant voltage source, the power supplied by the source
A) increases. B) decreases. C) does not change. D) increases for a time and then starts to decrease. |
increases
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Kirchhoff's loop rule is an example of
A) conservation of energy. B) conservation of charge. C) conservation of momentum. D) none of the given answers |
conservation of energy
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Three identical capacitors are connected in series to a battery. If a total charge of Q flows from the
battery, how much charge does each capacitor carry? A) 3Q B) Q C) Q/3 D) Q/9 |
Q
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When two or more capacitors are connected in parallel to a battery,
A) the voltage across each capacitor is the same. B) each capacitor carries the same amount of charge. C) the equivalent capacitance of the combination is less than the capacitance of any one of the capacitors. D) all of the given answers |
the voltage across each capacitor is the same
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As more and more capacitors are connected in parallel, the equivalent capacitance of the combination
increases. A) always true B) Sometimes true; it depends on the voltage of the battery to which the combination is connected. C) Sometimes true; it goes up only if the next capacitor is larger than the average of the existing combination. D) never true |
always true
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A resistor and a capacitor are connected in series to an ideal battery of constant terminal voltage. When
this system reaches its steady-state, the voltage across the resistor is A) greater than the battery's terminal voltage. B) less than the battery's terminal voltage, but greater than zero. C) equal to the battery's terminal voltage. D) zero. |
zero
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Three resistors of 12, 12, and 6.0 Ω are connected in series. A 12-V battery is connected to the
combination. What is the current through the battery? A) 0.10 A B) 0.20 A C) 0.30 A D) 0.40 A |
0.40 A
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A 14-A current flows into a series combination of a 3.0-Ω and a 4.0-Ω resistor. What is the voltage drop
across the 4.0-Ω resistor? A) 38 V B) 42 V C) 56 V D) 98 V |
56 V
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A 6.0-Ω and a 12-Ω resistor are connected in parallel to a 36-V battery. What power is dissipated by the
6.0-Ω resistor? A) 220 W B) 48 W C) 490 W D) 24 W |
220 W
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A 1.0-μF and a 2.0-μF capacitor are connected in series across a 3.0-V battery. What is the voltage across
the 2.0-μF capacitor? A) 3.0 V B) 2.0 V C) 1.0 V D) zero |
1.0 V
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) 1.0 μF, 2.0 μF, and 3.0 μF capacitors are connected in parallel across a 24-V battery. How much energy is
stored in this combination when the capacitors are fully charged? A) 1.7 mJ B) 2.1 mJ C) 4.8 mJ D) 7.1 mJ |
1.7 mJ
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A 2.0-μF capacitor is charged to 12 V and then discharged through a 4.0 × 106 Ω resistor. How long will
it take for the voltage across the capacitor to drop to 3.0 V? A) 8.0 s B) 11 s C) 22 s D) 24 s |
11 s
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A vertical wire carries a current straight down. To the east of this wire, the magnetic field points
A) north. B) east. C) south. D) down. |
south
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A current carrying circular loop of wire lies flat on a table top. When viewed from above, the current
moves around the loop in a counterclockwise sense. What is the direction of the magnetic field caused by this current, inside the loop? The magnetic field A) circles the loop in a clockwise direction. B) circles the loop in a counterclockwise direction. C) points straight up. D) points straight down. |
points straight up
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The force on a current-carrying wire in a magnetic field is equal to zero when
A) the current is parallel to the field lines. B) the current is at a 30° angle with respect to the field lines. C) the current is at a 60° angle with respect to the field lines. D) the current is perpendicular to the field lines. |
the current is parallel to the field lines
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A charged particle is observed traveling in a circular path in a uniform magnetic field. If the particle had
been traveling twice as fast, the radius of the circular path would be A) twice the original radius. B) four times the original radius. C) one-half the original radius. D) one-fourth the original radius. |
twice the original radius
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At a particular instant, a proton moves eastward at speed V in a uniform magnetic field that is directed
straight downward. The magnetic force that acts on it is A) zero. B) directed upward. C) directed to the north. D) directed to the south. |
directed to the north
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The magnetic field produced by a long straight current-carrying wire is
A) proportional to both the current in the wire and the distance from the wire B) proportional to the current in the wire and inversely proportional to the distance from the wire. C) inversely proportional to the current in the wire and proportional to the distance from the wire. D) inversely proportional to both the current in the wire and the distance from the wire. |
proportional to the current in the wire and inversely proportional to the distance from the wire
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At double the distance from a long current-carrying wire, the strength of the magnetic field produced by
that wire decreases to A) 1/8 of its original value. B) 1/4 of its original value. C) 1/2 of its original value. D) none of the given answers |
1/2 of its original value
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Two long parallel wires placed side-by-side on a horizontal table carry identical current straight toward
you. From your point of view, the magnetic field at the point exactly between the two wires A) points up. B) points down. C) points toward you. D) is zero. |
is zero
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A 2.0-m wire carrying a current of 0.60 A is oriented parallel to a uniform magnetic field of 0.50 T. What
is the magnitude of the force it experiences? A) zero B) 0.15 N C) 0.30 N D) 0.60 N |
zero
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A wire carries a current of 10 A in a direction of 30° with respect to the direction of a 0.30-T magnetic
field. Find the magnitude of the magnetic force on a 0.50-m length of the wire. A) 0.75 N B) 1.5 N C) 3.0 N D) 6.0 N |
0.75 N
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A proton moving at 4.0 × 104 m/s horizontally enters a region where a magnetic field of 0.13 T is present,
directed vertically downward. What force acts on the proton? A) zero B) 1.4 × 10-16 N C) 5.2 × 10-16 N D) 8.3 × 10-16 N |
8.3 × 10-16 N
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How much current must flow for 1.0 × 10-3 T of magnetic field to be present 1.0 cm from a wire?
A) 0.050 A B) 9.2 A C) 16 A D) 50 A |
50 A
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A high power line carrying 1000 A generates what magnetic field at the ground, 10 m away?
A) 4.7 × 10-6 T B) 6.4 × 10-6 T C) 2.0 × 10-5 T D) 5.6 × 10-5 T |
2.0 × 10-5 T
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How much current must pass through a 400 turn coil 4.0 cm long to generate a 1.0-T magnetic field at the
center? A) 0.013 A B) 13 A C) 40 A D) 80 A |
80 A
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An electric generator transforms
A) electrical energy into mechanical energy. B) mechanical energy into electrical energy. C) direct current into alternating current. D) alternating current into direct current. |
mechanical energy into electrical energy
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A transformer is a device used to
A) transform an alternating current into a direct current. B) transform a direct current into an alternating current. C) increase or decrease an ac voltage. D) increase or decrease a dc voltage. |
increase or decrease an ac voltage
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In a transformer, if the secondary coil contains more loops than the primary coil then it is a
A) step-up transformer. B) step-down transformer. |
step-up transformer
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In a transformer, the power input
A) is larger than the power output. B) is equal to the power output. C) is smaller than the power output. D) can be either larger or smaller than the power output. |
is equal to the power output
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2.0 A in the 100-turn primary of a transformer causes 14 A to flow in the secondary. How
many turns are in the secondary? A) 700 B) 114 C) 14 D) 4 |
14
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An ideal transformer has 60 turns on its primary coil and 300 turns on its secondary coil. If
120 V at 2.0 A is applied to the primary, what voltage is present in the secondary? A) 24 V B) 120 V C) 240 V D) 600 V |
600 V
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An ideal transformer has 60 turns on its primary coil and 300 turns on its secondary coil. If
120 V at 2.0 A is applied to the primary, what current is present in the secondary? A) 0.40 A B) 2.0 A C) 4.0 A D) 10 A |
0.40 A
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Faraday's law of induction states that the emf induced in a loop of wire is proportional to
A) the magnetic flux. B) the magnetic flux density times the loop's area. C) the time variation of the magnetic flux. D) current divided by time. |
the time variation of the magnetic flux
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Doubling the number of loops of wire in a coil produces what kind of change on the induced
emf, assuming all other factors remain constant? A) The induced emf is 4 times as much. B) The induced emf is twice times as much. C) The induced emf is half as much. D) There is no change in the induced emf. |
the induced emf is twice times as much
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According to Lenz's law, the direction of an induced current in a conductor will be that
which tends to produce which of the following effects? A) enhance the effect which produces it B) produce a greater heating effect C) produce the greatest voltage D) oppose the effect which produces it |
oppose the effect which produces it
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A circular loop of radius 0.10 m is rotating in a uniform magnetic field of 0.20 T. Find the
magnetic flux through the loop when the plane of the loop and the magnetic field vector are parallel. A) zero B) 3.1 × 10-3 T∙m2 C) 5.5 × 10-3 T∙m2 D) 6.3 × 10-3 T∙m2 |
zero
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A circular loop of radius 0.10 m is rotating in a uniform magnetic field of 0.20 T. Find the
magnetic flux through the loop when the plane of the loop and the magnetic field vector are perpendicular. A) zero B) 3.1 × 10-3 T∙m2 C) 5.5 × 10-3 T∙m2 D) 6.3 × 10-3 T∙m2 |
6.3 × 10-3 T∙m2
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A circular coil lies flat on a horizontal table. A bar magnet is held above its center with its
north pole pointing down, and released. As it approaches the coil, the falling magnet induces (when viewed from above) A) no current in the coil. B) a clockwise current in the coil. C) a counterclockwise current in the coil. D) a current whose direction cannot be determined from the information provided. |
a counterclockwise current in the coil
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The flux through a coil changes from 4.0 × 10-5 Wb to 5.0 × 10-5 Wb in 0.10 s. What emf
is induced in this coil? A) 5.0 × 10-4 V B) 4.0 × 10-4 V C) 1.0 × 10-4 V D) none of the given answers |
1.0 × 10-4 V
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The cross-sectional area of an adjustable single loop is reduced from 1.0 m2 to 0.50 m2 in
0.10 s. What is the average emf that is induced in this coil if it is in a region where B = 2.0 T upward, and the coil's plane is perpendicular to B? A) 5 V B) 10 V C) 15 V D) 20 V |
10 V
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In a vacuum, the velocity of all electromagnetic waves
A) is zero. B) is nearly 3 × 108 m/s. C) depends on the frequency. D) depends on their amplitude. |
is nearly 3 × 108 m/s
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Consider two spaceships, each traveling at 0.50c in a straight line. Ship A is moving
directly away from the Sun and ship B is approaching the Sun. The science officers on each ship measure the velocity of light coming from the Sun. What do they measure for this velocity? A) Ship A measures it as less than c, and ship B measures it as greater than c. B) Ship B measures it as less than c, and ship A measures it as greater than c. C) On both ships it is measured to be less than c. D) On both ships it is measured to be exactly c. |
On both ships it is measured to be exactly c
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How far does light travel in 1.0 μs?
A) 3.0 × 1014 m B) 0.30 km C) 3.0 m D) 30 cm |
0.30 km
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How far is a light year (the distance light travels in a year)?
A) 186,000 m B) 3.0 × 108 m C) 8.7 × 1013 m D) 9.5 × 1015 m |
9.5 × 1015 m
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Visible light ranges in wavelength from
A) 400 μm to 750 μm. B) 400 nm to 750 nm. C) 500 μm to 850 μm. D) 500 nm to 850 nm. |
400 nm to 750 nm
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What is the wavelength of a 92.9-MHz radio wave?
A) 32 mm B) 32 cm C) 3.2 m D) 32 m |
3.2 m
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What is the frequency of 20 mm microwaves?
A) 100 MHz B) 400 MHz C) 15 GHz D) 73 GHz |
15 GHz
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An electric field is produced by a
A) constant magnetic field. B) changing magnetic field. C) either a constant or a changing magnetic field. D) none of the given answers |
changing magnetic field
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Relative to a stationary observer, a moving clock
A) always runs slower than normal. B) always runs faster than normal. C) keeps its normal time. D) can do any of the above. It depends on the relative velocity between the observer and the clock. |
always runs slower than normal
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If you were to measure your pulse rate while in a spaceship moving away from the Sun at a
speed close to the speed of light, you would find that it was A) much faster than normal. B) much slower than normal. C) the same as it was here on Earth. |
the same as it was here on Earth
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A spaceship takes a nonstop journey to a planet and returns in 10 hours according to a clock
on the spaceship. If the speed of the spaceship is 0.80c, how much time has elapsed on the Earth? A) 3.2 h B) 7.0 h C) 15 h D) 17 h |
17 h
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Suppose one twin takes a ride in a space ship traveling at a very high speed to a distant star
and back again, while the other twin remains on Earth. The twin that remained on Earth predicts that the astronaut twin is A) younger. B) the same age. C) older. D) cannot be determined from the given information |
younger
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A set of twins, Andrea and Courtney, are initially 10 years old. While Courtney remains on
Earth, Andrea rides on a space ship which travels away from Earth at a speed of 0.6c for five years (as measured by Courtney), then turns around and comes back at 0.6c. When Andrea returns, Courtney is 20 years old. How old is Andrea upon her return? A) 10 years B) 12 years C) 18 years D) 20 years |
18 years
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Relative to a stationary observer, a moving object
A) appears shorter than normal. B) appears longer than normal. C) keeps its same length time. D) can do any of the above. It depends on the relative velocity between the observer and the object. |
appears shorter than normal
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As the speed of a particle approaches the speed of light, the mass of the particle
A) increases. B) decreases. C) remains the same. D) approaches zero. |
increases
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A meter stick is moving toward you with a speed of 0.80c. What is its length?
A) zero B) 0.40 m C) 0.60 m D) 1.0 m |
0.60 m
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What is the speed of a proton if its mass is twice its rest mass?
A) 0.50c B) 0.68c C) 0.73c D) 0.87c |
0.87c
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During a reaction, an element loses 4.8 × 10-28 kg of mass. How much energy (in Joules) is
released? A) 4.3 × 10-11 J B) 1.4 × 10-19 J C) 1.6 × 10-36 J D) 5.3 × 10-45 J |
4.3 × 10-11 J
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What is the momentum in kg∙m/s of a proton when it is moving with a speed of 0.60c?
A) 1.2 × 10-19 kg∙m/s B) 1.5 × 10-19 kg∙m/s C) 3.0 × 10-19 kg∙m/s D) 3.8 × 10-19 kg∙m/s |
3.8 × 10-19 kg∙m/s
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