Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
If neτ and m represent electron density, charge, relaxation time and mass of an electron respectively, then the resistance of a wire of length l and cross-sectional area A is
PhysicsCurrent ElectricityNEET
Options:
  • A mlne2τA
  • B mτAne2l
  • C ne2τAml
  • D ne2mlτA
Solution:
1931 Upvotes Verified Answer
The correct answer is: mlne2τA

R=ρlA

Since we know resistivity is given by ρ=mne2r

Resistance R=mlne2τA

where,
m= Mass of electron
l= length of conductor
n= charge density
e= charge of electron
τ= relaxation time
A= cross-sectional area

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.