Physical science moles Chapter 8

When a pair of 1 ohm resistors are connected in series, their combined resistance is

2 ohms, and when in parallel, 1/2 ohm

A 60-W light bulb is connected to a 120-V plug. What is the current in the light bulb?

0.5 A

If you use 10 J of work to push a charge into an electric field and then release the charge, as it flies past its starting position, its kinetic energy is

10 J

If you use 10 J of work to push a coulomb of charge into an electric field, its voltage with respect to its starting position is

10 V

A certain bulb with a resistance of 95 ohms is labeled "150 W." This bulb was designated for use in a

120-V circuit

Two charges separated by one meter exert a 1-N force on each other. If the charges are pushed to 0.25-m separation, the force on each charge will be

16 N

The source of electrons lighting an incandescent ac light bulb is

atoms in the light bulb filament

An electron and a proton

attract each other

The current in a 100-W bulb connected to a 120-V source is

None of the above

A woman experiences an electrical shock. The electrons making the shock come from the

Womans body

In a common dc circuit, electrons move at speeds of

a fraction of a centimeter per second

An uncharged pith ball is suspended by a nylon fiber. When a negatively charged rubber rod is brought nearby, without touching it, the pith ball

becomes polarized

Every proton in the universe is surrounded by its own

both of these

The electrical forces between charges depends on the

both of these

In an ac circuit, the electric field

changes magnitude and direction with time

An ampere is a unit of electrical

current

As more lamps are put into a series circuit, the overall current in the power source

decreases

A positive charge and a negative charge held near each other are released. As they move, the force on each particle

increases

As more lamps are put into a parallel circuit, the overall current in the power source

increases

Heat a copper wire and its electric resistance

increases

Charge carriers in a metal are electrons rather than protons because electrons are

loosely bound

A wire that carries an electric current

may be electrically charged

Rub electrons from your hair with a comb and the comb becomes

negatively charged

A difference between electric forces and gravitational forces is that electrical forces include

replusive interactions

In an electric circuit, the safety fuse is connected to the circuit in

series

To be safe in the unlikely case of a lightning strike, it is best to be inside a building framed with

steel

Compared to the amount of electric current that flows in the filament of a lamp, the amount of current that flows in the connecting wire is

the same

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

1 V

When a battery does 24 J of work on 10 C of charge, the voltage it supplies is

2.4 V

Coulomb's Law

a law stating that like charges repel and opposite charges attract, with a force proportional to the product of the charges and inversely proportional to the square of the distance between them.

Two lamps, one with a thick filament and one with a thin filament, are connected in parallel to a battery. The voltage is greatest across the lamp with the

both voltages are the same

Electrons move in an electrical circuit

by interacting with an established electric field

Stretch a copper wire so that it is thinner and the resistance between its ends

increases

To say that electric charge is conserved means that no case has ever been found where

is a whole-number multiple of the charge of one electron

To say that an object is electrically polarized is to say

its charges have been rearranged

Compared to the resistance of two resistors connected in series, the same two resistors connected in parallel have

less resistance

When a light switch is turned on in a dc circuit, the average speed of electrons in the lamp is

less than 1 cm/s

When two lamps are connected in parallel to a battery, the electrical resistance that the battery senses is

less than the resistance of either lamp

Compared to a single lamp connected to a battery, two lamps connected in parallel to the same battery will carry

more current

Connect a pair of lamps in series and you draw current from the connecting battery. Connect the same lamps in parallel and you draw

more current

A 10 ohm resistor has 5 A current in it. What is the voltage across the resistor?

more than 20 V

When two lamps are connected in series to a battery, the electrical resistance that the battery senses is

more than the resistance of either lamp

Strip electrons from an atom and the atom becomes a

positive ion

A positive ion has more

protons then electrons

A main difference between gravitational and electric forces is that electrical forces

repel or attract

The source of electrons in an ordinary electrical circuit is

the electrical conductor itself

There are electrons in the filament of the ac lamp in your bedroom. When you turn on the lamp and it glows, the glowing comes from

the same electrons

Two lamps, one with a thick filament and one with a thin filament, are connected in parallel to a battery. The current is largest in the lamp with the

thick filament

Compared to the filament thickness of a 60-W light bulb, the filament of a 100-W light bulb will be

thicker

A circuit is powered with a battery. Current flows

through both the battery and the rest of the circuit.

If you plug an electric toaster rated at 110-V into a 220-V outlet, current in the toaster will be about

twice what it should be

Alternating current is normally produced by a

generator

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

220 ohms

Two charges separated by 1 m exert a 1-N force on each other. If the charges are pulled to a

3-M separation distance, the force on each charge will be 0.11 N

The electrical force on a 2-C charge is 60 N. What is the value of the electric field at the place where the charge is located?

30 N/C

Two charges separated by 1 m exert a 1-N force on each other. If the magnitude of each charge is doubled, the force on each charge is

4 N

An electric heater is rated at 300 W when used in a 110-V circuit. The safety fuse in the circuit can handle 15 A of current. How many heaters can be safely operated in the circuit?

5

When a 10-V battery is connected to a resistor, 2 A of current flow in the resistor. What is the resistor's value?

5 ohms

A coulomb of charge that passes through a 6-V battery is given

6 joules

What is the power rating of a light bulb when 0.8 A flow through it when connected to a 120-V outlet?

96 W

Two charged particles repel each other will a force F. If the charge of one of the particles is doubled and the distance between them is also doubled, then the force will be

F/2

A balloon will stick to a wooden wall if the balloon is charged

either way

Which force binds atoms together to form molecules?

electrical force

A proton and an electron are placed in an electric field. Which undergoes the greater acceleration?

electron

A conductor differs from an insulator in that a conductor

none of these

What is the resistance of a 120-W incandescent lamp connected to a 120-V pow

none of these

A wire carrying a current is normally charged

not at all

Two charged particles held close to each other are released. As they move, the force on each particle increases. Therefore, the particles have

opposite signs

The headlights, radio, and defroster fan in an automobile are connected in

parallel with a switch for each

The number of electrons delivered daily to an average American home by an average power utility in the mid 1980s was

zero