CH 5 Electricity Study Guide

The amount of energy given to each coulomb of charge flowing through a 12-V battery is.. A) 12 J. B) 12 A. C) 12 V. D) all of the above E) none of the above

A) 12 J.

When a battery does 24 J of work on 10 C of charge, the voltage it supplies is... A) 2.4 V. B) 4.2 V. C) 24 V. D) 240 V. E) none of the above

A) 2.4 V.

A coulomb of charge passing through a 6-V battery acquires.. A) 6 joules. B) 6 amperes. C) 6 ohms. D) 6 watts. E) 6 newtons

A) 6 joules.

Which has the larger resistance, a 60-W or a 100-W incandescent lamp, both rated for 120- V operation? A) 60-W lamp B) 100-W lamp C) both the same

A) 60-W lamp

In a common dc circuit, electrons typically move at the speed of.. A) a fraction of a centimeter per second. B) a few meters per second. C) sound. D) light. E) none of the above

A) a fraction of a centimeter per second.

The direction of an electric field is defined as the direction of force on.. A) a positively-charged particle. B) a negatively-charged particle. C) any charged particle.

A) a positively-charged particle.

A sustained flow of electric charge requires.. A) a potential difference. B) a resistance. C) an electric field. D) electric polarization.

A) a potential difference.

An electron and a proton.. A) attract each other. B) repel each other. C) attract or repel depending on distance.

A) attract each other.

The pair of protons in the nucleus of a helium atom.. A) attracts a pair of orbiting electrons. B) repels orbiting electrons. C) both of these D) neither of these

A) attracts a pair of orbiting electrons

Direct current is normally produced by a.. A) battery. B) generator. C) both of these D) neither of these

A) battery.

Strictly speaking, it is correct to say that.. A) charge flows through a circuit. B) voltage flows through a circuit. C) resistance is established across a circuit. D) current causes voltage. E) all of these

A) charge flows through a circuit.

The electric force between charges is strongest when the charges are.. A) close together. B) far apart. C) either of these

A) close together.

More current will occur in a lamp when its filament is.. A) cold. B) hot. C) either cold or hot.

A) cold.

A proton and an electron placed in an electric field experience the same force. Which undergoes the greater acceleration? A) electron B) proton C) both equally D) none of the above

A) electron

In an electrically neutral atom the number of protons in the nucleus is equal to the number of.. A) electrons that surround the nucleus. B) neutrons in the nucleus. C) both of these D) none of the above

A) electrons that surround the nucleus.

A positive ion has a deficiency of.. A) electrons. B) neutrons. C) negative ions.

A) electrons.

The electric current in a copper wire is normally composed of.. A) electrons. B) protons. C) ions. D) all of the above

A) electrons.

The damage of electrical shock is predominantly due to.. A) excess current. B) an absence of voltage. C) reduced resistance. D) none of the above

A) excess current.

To say a circuit is dc is to say that current in the circuit.. A) has a single direction. B) alternates only slowly. C) is parallel to the connecting wires.

A) has a single direction.

Just as water flows from high to low pressure, electric charge flows from.. A) high to low voltage. B) high charge concentration to low charge concentration. C) high resistance to low resistance. D) all of the above E) none of the above

A) high to low voltage.

A positive and a negative charge near each other are released. As they move, the force on each particle.. A) increases. B) decreases. C) stays the same.

A) increases.

Which is more dangerous, touching a faulty 120-V light fixture, or a Van de Graaff generator charged to 100,000 V? A) light fixture B) generator C) both equally

A) light fixture

Compared to a single lamp connected to a battery, two lamps connected in parallel to the same battery will draw.. A) more current. B) less current. C) the same current.

A) more current.

As you comb your hair, electrons are rubbed onto the comb, which becomes.. A) negatively charged. B) positively charged. C) ionized.

A) negatively charged.

When you scuff electrons from a carpet onto your shoes, you become.. A) negatively charged. B) positively charged. C) polarized. D) ionized. E) neutralized.

A) negatively charged.

An electrical device that is "grounded" has.. A) no potential difference between it and the ground. B) an infinite potential difference between it and the ground. C) a firm connection to the ground. D) low voltage.

A) no potential difference between it and the ground.

If you strip electrons from an atom, the atom becomes a.. A) positive ion. B) negative ion. C) different element.

A) positive ion.

A negatively charged rod is brought near a metal can that rests on a wooden table. You touch the opposite side of the can momentarily with your finger. The can then becomes.. A) positively charged. B) negatively charged. C) uncharged.

A) positively charged.

The nucleus of an atom is charged.. A) positively. B) negatively. C) both of these D) none of the above

A) positively.

Voltage is most similar to.. A) pressure. B) current. C) resistance. D) all of the above E) none of the above

A) pressure.

Which of these has the greatest mass? A) proton B) electron C) both of these D) neither of these

A) proton

When the distance between two charges is halved, the electric force between the charges.. A) quadruples. B) doubles. C) is half. D) is reduced by one-quarter. E) none of the above

A) quadruples.

The safety fuse in an electric circuit is properly connected in.. A) series with the circuit. B) parallel to the circuit. C) either of these

A) series with the circuit.

If electrons were positive and protons were negative, Coulomb's law would be written.. A) the same. B) somewhat differently. C) very differently.

A) the same.

The electric field between oppositely-charged parallel plates is.. A) uniform. B) stronger at the ends. C) composed of field lines curved in opposite directions. D) none of the above

A) uniform

Compared to the mass of a proton, the mass of an electron is.. A) very much less. B) identical. C) greater.

A) very much less

Electric potential is measured in units of... A) volts. B) joules. C) amperes. D) watts. E) any or all of these

A) volts.

It takes 10 J of work to push a charge into an electric field. Relative to its starting position it has gained a potential energy of.. A) less than 10 J. B) 10 J. C) more than 10 J. D) none of the above

B) 10 J.

If you do 10 J of work to push 1 coulomb of charge into an electric field, its voltage with respect to its starting position is.. A) less than 10 V. B) 10 V. C) more than 10 V. D) none of the above

B) 10 V.

A pair of 1-ohm resistors connected in series has a combined resistance of.. A) 1 ohm. B) 2 ohms. C) 1/2 ohm. D) none of the above

B) 2 ohms.

The value of a resistor that carries 2 A when connected to 10 V is.. A) 2 ohms. B) 5 ohms. C) 10 ohms. D) 20 ohms. E) more than 20 ohms.

B) 5 ohms.

Electrons flow in a wire when there is.. A) an imbalance of charges in the wire. B) a potential difference across its ends. C) a difference in potential energy across its ends. D) none of the above

B) a potential difference across its ends.

Electric charge will flow in an electric circuit when... A) electric resistance is low. B) a potential difference exists. C) the circuit is grounded. D) electric devices in the circuit are not defective.

B) a potential difference exists.

The flow of charge in a circuit depends on.. A) adequate resistance. B) a potential difference. C) adequate chemical action. D) all of the above

B) a potential difference.

Which of these, both of the same length, has the greater electrical resistance? A) a thick copper wire B) a thin copper wire C) both about the same D) need more information

B) a thin copper wire

When you purchase a water pipe in a hardware store, water is not included. When you purchase copper wire, electrons.. A) must be supplied by you, just as water in a water pipe. B) already exist in the wire. C) may fall out, which is why wires are insulated. D) none of the above

B) already exist in the wire

Current that is typically 60 hertz is.. A) direct current. B) alternating current. C) either of these D) neither of these

B) alternating current.

The electric field in the wires of an ac circuit.. A) changes via the inverse square law. B) changes direction with time. C) remains relatively constant. D) is nonexistent. E) none of the above

B) changes direction with time

Food cooked in a microwave oven depends on electrical... A) conduction. B) charge polarization. C) resistance changes. D) field strength. E) all of the above

B) charge polarization.

An ampere is a unit of electric.. A) pressure. B) current. C) resistance. D) all of the above E) none of the above

B) current.

As more lamps are put into a series circuit, the overall current in the power source.. A) increases. B) decreases. C) stays the same.

B) decreases.

Alternating current is normally produced by a.. A) battery. B) generator. C) both of these D) neither of these

B) generator.

To say that an object is electrically polarized is to say.. A) it is electrically charged. B) its charges have been rearranged. C) its internal electric field is zero. D) it is only partially conducting. E) it is to some degree magnetic.

B) its charges have been rearranged.

Compared to a single lamp connected to a battery, two identical lamps connected in series.. to the same battery will draw A) more current. B) less current. C) the same current.

B) less current.

A rubber rod rubbed with fur becomes.. A) positively charged. B) negatively charged. C) both D) neither

B) negatively charged.

A bird can sit harmlessly on a high-voltage wire because.. A) the wire is insulated. B) no potential difference is across the birds feet. C) current is inside, not outside, the wire. D) the net charge on a current-carrying wire is zero. E) all of the above

B) no potential difference is across the birds feet.

Electric field lines about a point charge extend.. A) outward when the charge is negative. B) outward when the charge is positive. C) in circles.

B) outward when the charge is positive.

When you remove electrons from a metal cup, the cup becomes.. A) negatively charged. B) positively charged. C) ionized.

B) positively charged.

Two positively-charged plastic straws near each other tend to.. A) attract each other. B) repel each other. C) neutralize each other.

B) repel each other.

A main difference between gravitational and electric forces is that electric forces.. A) attract. B) repel or attract. C) obey the inverse-square law. D) act over shorter distances. E) are weaker

B) repel or attract.

A difference between electric and gravitational forces is that electric forces include.. A) separation distance. B) repulsive interactions. C) the inverse-square law. D) infinite range. E) none of the above

B) repulsive interactions.

Electric charge distributes itself on conducting surfaces.. A) with greater concentration on flat parts. B) such that the electric field inside is zero. C) both of the above D) none of the above

B) such that the electric field inside is zero.

Two charged particles near each other are released. As they move, the force on each particle increases. Therefore, the particles have... A) the same sign. B) the opposite sign. C) not enough information

B) the opposite sign

Compared to the amount of current that flows from a battery and into a circuit, the amount of current that returns to the battery is.. A) less. B) the same. C) greater. D) dependent on the internal resistance of the battery.

B) the same.

The vast numbers of electrons in a coin don't fly off the surface because.. A) mutual repulsion is incomplete. B) they are attracted by an equal number of protons. C) they are strongly bonded to their atoms. D) all of the above E) none of the above

B) they are attracted by an equal number of protons.

A term for electric pressure is.. A) current. B) voltage. C) electric resistance.

B) voltage.

Just as a sustained flow of water in a hydraulic circuit needs a pump, the flow of charge in an electric circuit needs 12.. A) current. B) voltage. C) resistance.

B) voltage.

When we think of electric potential difference, we are thinking about.. A) current. B) voltage. C) resistance.

B) voltage.

An electron is pushed into an electric field where it acquires a 1-V electrical potential. If two electrons are pushed the same distance into the same electric field, the electrical potential of the two electrons is.. A) 0.25 V. B) 0.5 V. C) 1 V. D) 2 V. E) 4 V.

C) 1 V.

It takes 10 J of work to push a charge initially at rest into an electric field. If the charge is then released, it flies back to its initial position with a kinetic energy of.. A) zero. B) 5 J. C) 10 J. D) more than 10 J. E) need more information.

C) 10 J.

The current through a 10-ohm resistor connected to a 120-V power supply is.. A) 1 A. B) 10 A. C) 12 A. D) 120 A. E) none of the above

C) 12 A

The current through two identical light bulbs connected in series is 0.25 A. The voltage across both bulbs is 110 V. The resistance of a single light bulb is.. A) 22 ohms. B) 44 ohms. C) 220 ohms. D) 440 ohms. E) none of the above

C) 220 ohms.

A length of wire has resistance R. The same kind of wire twice as long has resistance.. A) R/2. B) R. C) 2R D) none of the above

C) 2R

The power dissipated in a 4-ohm resistor carrying 3 A is.. A) 7 W. B) 18 W. C) 36 W. D) 48 W. E) not enough information

C) 36 W.

Two charged particles 1 m apart exert a 1-N force on each other. If the magnitude of each charge is doubled, the force on each particle will be.. A) 1 N. B) 2 N. C) 4 N. D) 8 N. E) none of the above

C) 4 N.

Two charged particles 1 m apart exert a 1-N force on each other. If the particles are instead 0.5 m apart, the force on each particle will be.. A) 1.0 N. B) 2.0 N. C) 4.0 N. D) 8.0 N. E) 16.0 N.

C) 4.0 N.

A coulomb of charge flowing in a bulb filament powered by a 6-volt battery is provided with.. A) 6 ohms. B) 6 amperes. C) 6 joules. D) 6 watts. E) 6 newtons

C) 6 joules.

Which of these scientists pioneered the study of electricity? A) Isaac Newton B) Galileo C) Benjamin Franklin D) all of the above

C) Benjamin Franklin

Two charged particles repel each other with a force F. If the charge of one particle is doubled and the distance between them is doubled, the force will be.. A) F. B) 2 F. C) F/2. D) F/4. E) none of the above

C) F/2.

The unit of resistance is named after.. A) Isaac Newton. B) Benjamin Franklin. C) Georg Simon Ohm. D) Micheal Faraday. E) Charles Coulomb.

C) Georg Simon Ohm.

The unit of electric charge, the coulomb, is the charge on.. A) one electron. B) one proton. C) a specific large number of electrons.

C) a specific large number of electrons.

The electric charge of all electrons.. A) vary from atom to atom. B) vary from ion to ion. C) are identical.

C) are identical.

A sustained electric current can be achieved with a.. A) generator. B) battery. C) both D) none of the above

C) both

The unit of measurement for electric power is.. A) joules per second. B) watts. C) both are equivalent D) none of the above

C) both are equivalent

A suitable electric pump in an electric circuit is a.. A) chemical battery. B) generator. C) both of these D) neither of these

C) both of these

An electrically polarized object normally has.. A) a net charge of zero. B) displaced charges. C) both of these D) none of the above

C) both of these

Current in a conductor can be increased by.. A) increasing the voltage across it. B) reducing its resistance. C) both of these D) neither of these

C) both of these

Every proton in the universe is surrounded by its own.. A) electric field. B) gravitational field. C) both of these D) none of the above

C) both of these

Normally a balloon charged to several thousand volts has a relatively small amount of.. A) charge. B) energy. C) both of these D) none of the above

C) both of these

Ohm's law tells us that the amount of current produced in a circuit is.. A) directly proportional to voltage. B) inversely proportional to resistance. C) both of these D) neither of these

C) both of these

The electric force between charges depends on the.. A) magnitude of electric charges. B) separation distance between electric charges. C) both of these D) none of the above

C) both of these

Electric potential is the ratio of electric energy to the amount of electric... A) current. B) resistance. C) charge. D) voltage. E) none of the above

C) charge.

A balloon will stick to a wooden wall if the balloon is charged... A) negatively. B) positively. C) either of these D) none of the above

C) either of these

Which force binds atoms together to form molecules? A) gravitational B) nuclear C) electric D) centripetal E) none of the above

C) electric

Heat a copper wire and its electrical resistance.. A) decreases. B) remains unchanged. C) increases.

C) increases.

The flow of electrons in an electric circuit move by.. A) bumping other electrons. B) colliding with molecules. C) interacting with an established electric field. D) none of the above

C) interacting with an established electric field.

When the voltage across a steady resistance is doubled, the current.. A) is half. B) remains the same. C) is doubled D) is quadrupled.

C) is doubled

When a steady voltage is across one-half as much resistance, the current.. A) is half. B) remains the same. C) is doubled. D) is quadrupled.

C) is doubled.

Strictly speaking, it is correct to say that voltage.. A) flows through a circuit. B) flows across a circuit. C) is impressed across a device in a circuit. D) all of these

C) is impressed across a device in a circuit.

Charge carriers in a metal are electrons rather than protons because electrons are.. A) negative. B) smaller. C) loosely bound. D) all of the above E) none of the above

C) loosely bound.

Much of the charge on a conducting cube is.. A) uniformly spread over its surface. B) partly beneath the surface. C) mutually repelled toward its corners. D) none of the above

C) mutually repelled toward its corners.

To say that electric charge is conserved means that no case has ever been found where.. A) the net charge on an object has changed. B) the net amount of charge on an object has increased. C) net charge has been created or destroyed. D) none of the above

C) net charge has been created or destroyed.

Which of these does not have an electrical charge? A) proton B) electron C) neutron D) all of the above E) none of the above

C) neutron

Two charged particles near each other are released. As the particles move, the velocity of each increases. Therefore, the particles have... A) the same sign. B) the opposite sign. C) not enough information

C) not enough information

The purpose of a voltage source is to provide an electrical.. A) energy sink. B) field. C) pressure.

C) pressure.

In a circuit powered by a battery it is correct to say that electrons flow.. A) from the battery and into the circuit. B) from the negative terminal to the positive terminal of the battery. C) through both the battery and the devices making up the circuit. D) none of the above

C) through both the battery and the devices making up the circuit.

The purpose of the third prong on a common electric plug of an appliance is.. A) to handle three-phase electricity. B) to provide an alternate live wire. C) to connect the appliance to zero ground potential. D) a substitute for a safety fuse. E) all of the above

C) to connect the appliance to zero ground potential.

What is the power rating of a device that draws 0.8 A when connected to 120 V? A) 12 W B) 15 W C) 60 W D) 96 W E) 120 W

D) 96 W

A negatively-charged balloon touching a wooden wall.. A) pulls positive charge on the wall surface toward it. B) pushes negative charge in the wall away from it. C) polarizes molecules in the wall. D) all of the above E) none of the above

D) all of the above

The different outcomes in touching a faulty 120-V light fixture and a high-voltage Van de Graaff generator have to do with differences in... A) sustainability of charge flow. B) duration of charge flow. C) amount of energy transferred. D) all of the above E) none of the above

D) all of the above

The electric field lines between a pair of equal and opposite charges are.. A) directed from positive to negative. B) more concentrated closer to the charges. C) vectors, with patterns resulting from the inverse-square law. D) all of the above E) none of the above

D) all of the above

To say that electric charge is conserved is to say that electric charge.. A) occurs in an infinite variety of quantities. B) is a whole-number multiple of the charge of one electron. C) will interact with neighboring electric charges. D) can neither be created nor destroyed.

D) can neither be created nor destroyed.

The fundamental force underlying all chemical reactions is.. A) gravitational. B) nuclear. C) centripetal. D) electrical. E) none of the above

D) electrical.

The source of electrons in an ordinary electric circuit is.. A) a dry cell, wet cell, or battery. B) usually a wall socket. C) a generator at the power station. D) the electric conductor itself. E) none of the above

D) the electric conductor itself.

If you plug a 110-V electric toaster into a 220-V outlet, current in the toaster will be about.. A) half what is should be. B) the same as if it were plugged into a 110-V outlet. C) more than twice what it should be. D) twice what it should be.

D) twice what it should be.

Two charged particles 1 m apart exert a 1-N force on each other. If the particles are instead 0.25-m apart, the force on each particle will be... A) 1.0 N. B) 2.0 N. C) 4.0 N. D) 8.0 N. E) 16.0 N.

E) 16.0 N.

The electric power of a lamp that carries 2 A at 120 V is.. A) 1/6 W. B) 2 W. C) 60 W. D) 20 W. E) 240 W.

E) 240 W

The voltage across a 10-ohm resistor carrying a current of 5 A is.. A) 2 V. B) 5 V. C) 10 V. D) 20 V. E) more than 20 V.

E) more than 20 V.

The electric field around an isolated electron has a certain strength at a 1-cm distance from the electron. The electric field strength 2 cm from the electron is... A) half as much. B) the same. C) twice as much. D) four times as much. E) none of the above

E) none of the above