Finding Systematic Error
BlackBoard Notes

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======================= First Board Section =============================

• Recall - reults of Ohm's Law experiment:
  • Everyone found R₁ + R₂ < R_set. Why?
  • 

======================= Second Board Section =============================

• From "Ohm's Law" instructions (pg. 2 - Analysis):
  • "For most single solid materials at constant temperature, the relation between current and voltage is linear,…"

======================= Third Board Section =============================

• Drude Model of conductivity:     σ_c ∝ nτ      (See Moore, sec. E5.2 and problem E5R.1)

• σ_c ≡ conductivity ("sigma")
• n ≡ number of charge carriers per m³
• τ ≡ time between collisions ("tau")
• Conductors (metals): τ decreases with increasing Temperature, so σ_c decreases, and Resistance increases
• Semiconductors (carbon): τ still decreases (a little) with increasing T, but n greatly increases, so σ_c increases and R decreases

======================= Fourth Board Section =============================

• Note that the wire does not connect through the carbon resistor:
  • 

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