Electricity

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The value of a resistor used in the parallel circuit is [______] Ω.

-24

Which are disadvantages of series circuits? Check all that apply.

-A break in one wire causes all current to stop. -If one bulb goes out, the others go out.

Which statements best characterize conductors? Check all that apply.

-Conductors allow electricity to easily move through them. -Metal is an example of a conductor.

Which changes would cause an increase in the resistance of a wire? Check all that apply.

-increasing its temperature -using a longer wire -using a thinner wire

An electric force exists between which pair of objects? Check all that apply. a neutral object and a negative object two negative objects a neutral object and a positive object two positive objects a negative object and a positive object two neutral objects

-two negative objects -two positive objects -a negative object and a positive object

What is the current in the 50 Ω resistor?

1.2 A

What is the value of R₃?

10 Ω

A ceiling fan draws a current of 0.625 A and has a voltage of 120 V. The resistance of the ceiling fan, to the nearest whole number, is [___________] Ω.

192

A source charge generates an electric field of 1236 N/C at a distance of 4 m. What is the magnitude of the source charge?

2.2 µC

A charge of 8.5 × 10⁻⁶ C is in an electric field that has a strength of 3.2 × 10⁵ N/C. What is the electric force acting on the charge?

2.7 N

What is the strength of the electric field 0.020 m from a 12 µC charge?

2.7 × 10⁸ N/C

A charge of 6.4 × 10⁻⁷ C experiences an electric force of 1.8 × 10⁻¹ N. What is the electric field strength?

2.8 × 10⁵ N/C

The strength of the electric field 0.5 m from a 6 µC charge is [________] N/C. (Use k = 8.99 × 10⁹ N• and round answer to the nearest whole number.)

215760

A wire delivers 12.0 C of charge in 4.0 s. What is the current in the wire?

3.0 A

A source charge generates an electric field of 4286 N/C at a distance of 2.5 m. What is the magnitude of the source charge?

3.0 µC

What is the value of the charge that experiences a force of 2.4 × 10⁻³ N in an electric field of 6.8 × 10⁻⁵ N/C?

3.5 × 10¹ C

What is the electric potential energy of a charge that experiences a force of 3.6 × 10⁻⁴ N when it is 9.8 × 10⁻⁵ m from the source of the electric field?

3.5 × 10⁻⁸ J

A circuit has a resistance of 2.5 Ω and is powered by a 12.0 V battery. The current in the circuit, to the nearest tenth, is [___________] A.

4.8

The magnitude of the net electrical force acting on the +6 µC charge, rounded to the tenths place, is [_________] N.

5.4

A charge of +0.08 C moves to the right due to a 4 N force exerted by an electric field. What is the magnitude and direction of the electric field?

50 N/C right

The magnitude of the electrical force acting between a +2.4 × 10-8 C charge and a +1.8 × 10-6 C charge that are separated by 0.008 m is [__________] N, rounded to the tenths place.

6.1

In 12 s, a wire delivers 96 C of charge. The current in the wire, to the nearest whole number, is [___________] A.

8

A current of 6.0 A runs through a circuit for 2.5 minutes. How much charge was delivered to this circuit?

900 C

How does charging by conduction occur?

A charged object touches a neutral object.

Which statement correctly describes the formation of an electric current?

A voltage causes electric charges to move from higher to lower potential.

What can he expect to see?

All bulbs in circuit 1 will shine more dimly than the original bulbs, while all bulbs in circuit 2 will have the same brightness as the original bulbs.

Which statements are correct? Check all that apply. Charge Q is positive. Charge Q is negative. The electric field is uniform. The electric field is nonuniform. If charge A is negative, it moves away from charge Q. If charge A is positive, it moves away from charge Q. (A is negative) . . ↓ →Q←•A . . ↑

Charge Q is negative. The electric field is nonuniform. If charge A is negative, it moves away from charge Q.

What formula gives the strength of an electric field, E, at a distance from a known source charge?

E = kq/d²

What is the equation for calculating the electrical force, Fe, between two charges?

Fe = kq₁q₂/d²

Which equation relates charge, time, and current?

I = Δq/t

How does the electrical force relate to the charge of an object?

It is directly proportional to the charge.

How does the electrical force relate to the distance between two charged objects?▫️

It is inversely proportional to the square of the distance.

How does a rubber rod become negatively charged through friction?

It is rubbed with another object, and electrons move onto the rod.

How does the skit model a method of charging?

It models induction because the offer of flowers represents a charged object that causes an electron (a flower) to transfer from one object to another.

How will the electrical force between the charges compare with the original force?

It will decrease to one-sixth the original force.

Cici uses a long extension cord to plug a lamp into a wall outlet in the next room. What effect will the extension cord have on the circuit?

It will increase the resistance in the circuit.

Which best describes the electric field created by a positive charge?▫️

Its rays point away from the charge.

In which regions should Jason place each label?▫️

Label 1: X Label 2: Z

In which region should she place each label? Label 1: Current flows in the circuit. Label 2: This forms when a bulb burns out. Open circuit: W,X Closed circuit: Y,Z Short circuit: X,Y

Label 1: Y Label 2: W

For a constant voltage, how is the resistance related to the current?

Resistance is inversely proportional to current, so when the resistance doubles, the current is cut in half.

In a movie, the heroine saves the day by cutting a wire before the time runs out on a timer. How did she change the circuit?

She changed a closed circuit to an open circuit.

Which best describes the spheres?

Sphere A is negative and sphere B is positive because electrons from sphere B are attracted to the rod and move to sphere A.

Jason sees a news report about a traffic jam caused by a truckload of tires that spilled across the road. The next day in class, he uses the traffic jam as an analogy to explain electric circuits to his friend. Which is most likely the analogy that Jason used?

The cars represent moving charges, and the spilled tires represent an increased resistance that causes the current to decrease.

A negative test charge experiences a force to the right as a result of an electric field. Which is the best conclusion to draw based on this description?

The electric field points to the left because the force on a negative charge is opposite to the direction of the field.

How do the electrical force and the gravitational force compare?

The electrical force is 1.2 × 10³⁶ times greater than the gravitational force, but only the gravitational force is attractive.

Which statements correctly compare the gravitational force with the electrical force? Check all that apply. The gravitational force can be repulsive. The gravitational force can be attractive. The electrical force can be repulsive. The electrical force can be attractive. Any two objects experience a gravitational force between them. Any two objects experience an electrical force between them.

The gravitational force can be attractive. The electrical force can be repulsive. The electrical force can be attractive. Any two objects experience a gravitational force between them.

How do the gravitational and electrical forces between a proton and a neutron compare?

The gravitational force is much larger than the electrical force for any distance between the particles.

Which change should Rolanda suggest to her friend to correct the error?

The note about infinite reach belongs in region Y.

How do the charges compare when two objects are charged through friction?

The objects become oppositely charged and have equal amounts of charge.

Which statement best explains the likely cause of the fire?

The wiring contained a short circuit, so the reduced resistance caused an increase in current.

Both the electrical force and the gravitational force between two objects share which relationship?

They are inversely proportional to the square of the distance.

Which statements about electric field lines are correct? Check all that apply.

They point toward a negative charge. They point away from a positive charge. They never cross.

Which circuit component should Keisha use to start or stop the current in the circuit?

W

Which diagram is correct?

W

Which vector best represents the net force acting on the -3 C charge in the diagram?

W

Which vector best represents the net force acting on the +4 C charge in the diagram?

X

Bruce must report any circuits that deliver more than 4.0 C of charge in 8.0 s. Which lists every circuit that Bruce must include in his report?

X and Z

She knows that a magnesium ion has an electric field that points away from the ion. What values should she use to complete her table?

X: 12 Y: 12 Z: 10

Which labels belong in the regions marked X and Y?

X: Decreasing to half will quadruple force Y: Doubling will double force

What are the charges of objects X and Y?

X: positive Y: negative

At which point is the electric field strongest? . . . . . . .↑W . . . . . . . .I . . . . . . . .I Z-----Y(+)-→X

Y

If the force between two charges, q, separated by a distance, d, is F, what is the list of the other forces, from greatest to least?

Y, W, X, Z

A 7.2 × 10⁻⁵ C charge has an electric potential energy of 1.08 × 10⁻² J. The electric potential, to the nearest whole number, is [______________] V.

_150

Which formulas belong in the regions marked X and Y?

_X: Req = R1 + R2 + R3 Y: I = V/Req X: I = I1 = I2 = I3 Y: V = V1 + V2 + V3 X: I = V/Req Y: V = V1 = V2 = V3

Electric field lines can never cross. What would crossed electric field lines indicate?

a field pointing in two directions

Which best describes the materials that make up an electrical cord?

a metallic conductor with free electrons surrounded by a rubber insulator lacking free electrons

A circuit featuring multiple paths through which current can flow is best classified into which category?

a parallel circuit

What type of circuit does this traffic situation model?

a parallel circuit because there is more than one path

An electric field is represented by the force on which particle?

a positive test charge

A circuit that has only a single path for current to flow through is best classified into which category?

a series circuit

What is the unit for measuring electric current?

ampere

How should she draw the field lines?

away from the positive charge and toward the negative charge

-| | - Which circuit component does the symbol represent?

battery

Which change would make the diagram correct?

changing the force to point right

Which factors affect the electrical force between two objects?

charge and distance between them

Through which element would someone most likely receive a shock?

chromium (Cr)

What is the continuous flow of electric charge?

current

A pair of opposite electric charges of equal magnitude is called a(n)

dipole.

What is a path through which electric charges travel?▫️

electric circuit

The area around a charged object that can exert a force on other charged objects is an electric [____________].

field

When studying atoms, scientists can ignore the [________________] force between charged particles that make up the atoms because it is many millions of times smaller than other forces in the atom.

gravitational

A material that restricts the flow of electricity or thermal energy is a(n) [_________________].

insulator

What is the direction of the electric field at a point directly to the left of a positive charge, Q?

left

A positive charge, q₁, of 5 µC is 3 × 10⁻² m west of a positive charge, q₂, of 2 µC. What is the magnitude and direction of the electrical force, Fe, applied by q₁ on q₂?

magnitude: 100 N direction: east

A negative charge, q₁, of 6 µC is 0.002 m north of a positive charge, q₂, of 3 µC. What is the magnitude and direction of the electrical force, Fe, applied by q₁ on q₂?

magnitude: 4 × 10⁴ N direction: north

What is the unit for resistance?

ohm

What is the tendency of a material to oppose the flow of charge?

resistance

A disrupted circuit in which the current bypasses its proper path is a(n) [_________________] circuit.

short

Which quantities are equal to total of the individual values within a circuit?

the current in a parallel circuit and the voltage in a series circuit

Which correctly describes the number of one type of component in this circuit?

three resistors

How did Tracy become charged?

through friction between her feet and the carpet

What is the purpose of the component represented by the symbol? --( V )--▫️

to measure voltage

What is the direction of the electric field at a point directly below a negative charge, Q?

🚫left _right


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