NEET-XII-Physics

neet 2020 questions with solutions year:2020

with Solutions - page 2
  • #20
    The mean free path for a gas, with molecular diameter `` d `` and number density `` n `` can be expressed as :
    (A) `` \frac {1}{\sqrt{2} n \pi d} ``
    (B) `` \frac {1}{\sqrt{2} n \pi d^2} ``
    (C) `` \frac {1}{\sqrt{2} n^2 \pi d^2} ``
    (D) `` \frac {1}{\sqrt{2} n^2 \pi^2 d^2} ``
    digAnsr:   B
    Ans : Mean free path for a gas sample `` \lambda_{m}=\frac{1}{\sqrt{2}\pi d^{2} n} ``
    where d is diameter of a gas molecule and n is molecular density