Understanding Resistance and Resistivity

What is resistivity and how is it defined?

• Resistivity is the total energy consumed by a material during electrical conduction.

• Resistivity is a measure of how easily a material can be magnetized.

• Resistivity is the speed at which electric current flows through a conductor.

• Resistivity is a measure of a material's resistance to electric current, defined as resistance per unit length and area.

List three factors that affect the resistivity of a material.

• Magnetism, sound, light

• Temperature, material type, impurities

• Voltage, pressure, length

• Color, density, shape

How does temperature influence the resistivity of conductors?

• Temperature increases resistivity in conductors.

• Higher temperatures lead to lower resistivity in conductors.

• Temperature has no effect on the resistivity of conductors.

• Temperature decreases resistivity in conductors.

Explain how impurities in a material can affect its resistivity.

• Impurities only affect the thermal conductivity, not the resistivity.

• Impurities decrease resistivity by enhancing charge carrier mobility.

• Impurities increase resistivity by scattering charge carriers, reducing their mobility.

• Impurities have no effect on resistivity in materials.

Compare the resistivity of metals and insulators.

• Metals have low resistivity; insulators have high resistivity.

• Metals and insulators have variable resistivity depending on temperature.

• Metals have high resistivity; insulators have low resistivity.

• Both metals and insulators have the same resistivity.

How does the length of a conductor affect its resistance?

• The length of a conductor has no effect on its resistance.

• The longer the conductor, the higher its resistance.

• The longer the conductor, the lower its resistance.

• Resistance is only affected by the material of the conductor.

What role does cross-sectional area play in resistance?

• Cross-sectional area has no effect on resistance.

• A smaller cross-sectional area decreases resistance.

• A larger cross-sectional area decreases resistance.

• A larger cross-sectional area increases resistance.

Define the term 'resistance' in the context of electrical circuits.

• Resistance is the speed at which current flows through a conductor.

• Resistance is the total amount of power consumed in a circuit.

• Resistance is the opposition to the flow of electric current in a circuit.

• Resistance is the measure of voltage in a circuit.

What is the formula for calculating resistance using resistivity?

• R = ρ(L×A)

• R = ρ(A/L)

• R = ρ(L/A)

• R = ρ(A+L)

Identify a material with high resistivity and its application.

• Rubber; used for electrical insulation.

• Wood; used for furniture.

• Copper; used for water pipes.

• Aluminum; used for cooking utensils.