SUMMARY
The discussion centers on how resistance per unit length varies in a current-carrying ohmic metal wire as its cross-sectional area decreases. It is established that while the current remains constant, the current density increases as the cross-sectional area (A) decreases, leading to a corresponding increase in the electric field. This results in a higher voltage across the wire, indicating that resistance does not remain constant but instead varies with changes in cross-sectional area.
PREREQUISITES
- Understanding of Ohm's Law and its components (voltage, current, resistance).
- Familiarity with the concept of current density (J = I/A).
- Knowledge of electric fields and their relationship with current density.
- Basic principles of conductive materials and their behavior under electrical stress.
NEXT STEPS
- Study the relationship between current density and electric field in conductive materials.
- Explore the mathematical derivation of resistance in varying cross-sectional areas.
- Learn about the implications of resistance changes in practical applications, such as electrical wiring.
- Investigate the effects of temperature on resistance in conductive materials.
USEFUL FOR
Students studying electrical engineering, physics enthusiasts, and professionals involved in electrical circuit design and analysis.