Physics · Ohm's law, electrical resistance, I-V characteristics of Ohmic and non-ohmic conductors

Wire of a certain material is stretched slowly be dep10. Its new resistance and

Wire of a certain material is stretched slowly be dep10. Its new resistance and specific resistance becomes respectively.

  • A. Both remain same
  • B. 1.1 times in both
  • C. 1.2 times, 1.1 times
  • D. 1.21 times, same

Step-by-step solution

When a wire is stretched slowly, volume remains constant. If length increases by 10% (factor 1.1), cross-sectional area decreases by factor 1/1.1. Resistance R = ρL/A, so new resistance R' = ρ(1.1L)/(A/1.1) = 1.21ρL/A = 1.21R. Specific resistance (resistivity) depends only on material and temperature, which are unchanged, so it remains same.
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