Resistance and Ohm's Law

Resistance

The measure of the opposition to current flow in an electrical circuit.

Conductors

Materials that offer very little resistance where electrons can move easily.

Insulators

Materials that present high resistance and restrict the flow of electrons.

Lower

Higher resistance means _____ current flow. If abnormally high, one possible cause could be damaged conductors due to burning or corrosion.

Higher

Lower resistance means _____ current flow. Possible causes include insulators damaged by moisture or overheating.

Length

A direct relationship exists between the amount of resistance encountered by charge and the ______ of wire it must traverse.

Longer

The _____ the wire, the more resistance there will be.

Shorter

The ______ the wire, the lesser is the resistance it would offer

Thicker

The _______ the wire, the less resistance that there will be to the flow of electric charge.

Cross-Sectional Area

Thicker wires have a greater _____-________ area.

Thinner

The _______ the wire, the higher is the resistance met by the charges as they move through the wire.

Silver

This material is one of the best conductors but is never used in wires of household circuits due to its cost.

Copper and aluminum

These are among the least expensive materials with suitable conducting ability to permit their use in wires of household circuits.

Resistivity

The ________ of a material is dependent upon the material's electronic structure and its temperature.

Resistor

A passive two-terminal electrical component that implements electrical resistance as a circuit element.

Limits

The resistor's resistance _____ the flow of electrons through a circuit.

Passive components

Resistors are ______ __________, meaning they only consume power.

Ohm’s Law

This law states that the electric current through a conductor between two points is directly proportional to the voltage across the two points.

Current

Refers to the continuous movement of electric charge or flow through the conductors of a circuit.

Voltage

Refers to the force motivating charge carriers to “flow” in a circuit.