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Zorluk: KolayResistance and Resistivity

In electrical circuits, the physical characteristics of a conductor govern its opposition to current flow. Match each conductor modification on the left with its resulting effect on electrical resistance on the right.

  • Extending the physical length of the wireIncreases resistance because electrons must traverse a longer conductive path
  • Increasing the wire diameter (larger cross-sectional area)Decreases resistance because a wider cross-section provides more parallel pathways for electron flow
  • Elevating the operating temperature of a standard copper wireIncreases resistance because increased lattice vibrations cause more frequent electron collisions
  • Replacing copper with nichrome of identical dimensionsIncreases resistance because the substitute alloy has a significantly higher intrinsic resistivity

Cevap

Extending length matches with increasing resistance due to a longer path; increasing diameter matches with decreasing resistance due to a wider cross-section; elevating temperature matches with increasing resistance due to increased atomic vibrations; replacing copper with nichrome matches with increasing resistance due to higher intrinsic resistivity.
Each modification is correctly paired according to the fundamental resistance formula R=ρLAR = \rho \frac{L}{A} and the positive temperature coefficient of metallic conductors: increasing length increases RR, increasing cross-sectional area decreases RR, heating the metal increases RR, and selecting a higher resistivity material increases RR.

Adım Adım Çözüm

1
Analyze the relationship between wire length and resistance using R=ρLAR = \rho \frac{L}{A}
Resistance increases linearly as length increases.
Electrons encounter more resistive material over a longer distance.
2
Analyze the relationship between wire cross-sectional area (thickness) and resistance
Resistance decreases as area increases.
A greater cross-sectional area allows more electrons to pass simultaneously with fewer collisions.
3
Determine the effect of thermal energy on metallic conductors
Resistance increases as temperature rises.
Thermal energy causes metal lattice ions to vibrate more vigorously, impeding the drift of free electrons.
4
Compare material resistivity (ρ\rho) between copper and nichrome
Nichrome creates greater resistance than copper of identical dimensions.
Nichrome is a high-resistivity alloy specifically designed to impede current flow and generate heat.

Anahtar Kavram

The resistance of a conductor is determined by its physical dimensions (length and cross-sectional area), material resistivity, and operating temperature.
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Resistance and Resistivity

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