5.2 Resistivity

• Resistivity is an intrinsic property of a material.


  True
• What is the symbol for resistivity?

  ρ (rho)
• Resistivity is the measure of a material's opposition to current flow
• Copper has a low resistivity, making it a good conductor.


  True
• What is the formula for calculating resistivity?

  ρ = RA/L
• Arrange materials by increasing resistivity

  1️⃣ Copper

  2️⃣ Silicon

  3️⃣ Rubber
• How does temperature affect the resistivity of metals?

  Resistivity increases
• Pressure and impurities have a significant effect on resistivity.

  False
• Resistivity is a measure of a material's opposition to current flow
• What is the formula for resistivity?

  $\rho =$$RA / L$
• What is the resistivity of a copper wire with a resistance of 0.01 Ω, a cross-sectional area of 1 mm², and a length of 5 meters?

  $2 \times 10^{ - 9} \, \Omega \, \text{m}$
• How does temperature affect the resistivity of metals?

  Increases resistivity
• The resistivity of insulators is higher than that of conductors.


  True
• What three variables must be known to calculate resistivity using the formula ρ = RA/L?

  R, A, and L
• What is resistivity a measure of?

  Resistance to electric current
• Resistivity depends only on the type of material
• What are the units for resistivity?

  Ohm-meters (Ω m)
• What does resistance depend on in addition to the material?

  Material and dimensions
• Rubber has a high resistivity, making it a good insulator
• Resistivity is directly related to the cross-sectional area
• Match the material type with its resistivity

  Good conductors ↔️ Low resistivity

  Semiconductors ↔️ Moderate resistivity

  Insulators ↔️ High resistivity
• In semiconductors, resistivity generally decreases with increasing temperature
• What is the symbol used for resistivity?

  $\rho$
• Resistance depends only on the material type.

  False
• Resistivity is inversely related to the material's length
• Arrange the following materials by increasing resistivity:

  1️⃣ Copper

  2️⃣ Silicon

  3️⃣ Rubber
• The resistivity of semiconductors generally decreases with increasing temperature
• Match the material category with its resistivity range:

  Conductors ↔️ 10^{-8} \, \text{to} \, 10^{-6} \, \Omega \, \text{m}</latex>

  Semiconductors ↔️ $10^{ - 5} \, \text{to} \, 10^{2} \, \Omega \, \text{m}$

  Insulators ↔️ $10^{10} \, \text{to} \, 10^{14} \, \Omega \, \text{m}$
• The formula for resistivity is \rho = (RA) / L