Electric Current

The chart shows the voltage of four electric currents.

Which is best supported by the data in the chart?

• Current W flows at a higher rate than Current Z.

• Current Y flows at a lower rate than Current X.

• Current X has a lower potential difference than Current Y.

• Current Z has a greater potential difference than Current W.

Which two wire properties would provide the greatest resistance to the flow of a current?

• short, thin

• long, thin

• hot, thick

• cool, thick

What is required for an electric charge to flow through a wire?

• zero resistance in the wire

• a balance of electric potential

• high resistance in the wire

• a difference in electric potential

Potential difference is measured in units called _____.

• ohms

• volts

• charges

• amperes

Measurements of two electric currents are shown in the chart.

Which best compares the two currents?

• Current X has a greater potential difference, and the charges flow at a slower rate.

• Current Y has a greater potential difference, and the charges flow at a slower rate.

• Current X has a greater potential difference, and the charges flow at a faster rate.

• Current Y has a greater potential difference, and the charges flow at a faster rate.

Which most likely has the greatest conductivity?

• a warm plastic rod

• a cool rubber tube

• a cool lead metal strip

• a warm copper wire

In the diagram, the arrow shows the movement of electric charges through a wire connected to a battery.

What causes the electric charges to flow from one end of the battery to the other?

• a balance in electric potential

• a balance in resistance

• a difference in electric potential

• a difference in resistance

Resistance depends on which properties of a wire? Check all that apply.

• color

• thickness

• length

• temperature

• texture

What would decrease the resistance of wires carrying an electric current?

• shorter wires

• higher-temperature wires

• darker-colored wires

• thinner wires

Electric current is the flow of charged particles called _______.

• protons

• electrons

• neutrons