Random Walk/Brownian motion/Diffusion — CSIR Net PYQ (Question 2)

A Random Walk/Brownian motion/Diffusion previous-year question (PYQ) from Statistical Mechanics (CSIR Net). Read the question, check the correct answer, then practise the full topic.

Question 2 of 15 · 5.0 marks

A large number

N

of Brownian particles in one dimension start their diffusive motion from the origin at time

t = 0

. The diffusion coefficient is

D

. The number of particles crossing a point at a distance

L

from the origin, per unit time, depends on

L

and time

t

1 $\frac{N}{4 π D t} e^{- L^{2} / (4 D t)}$
2 $\frac{N L}{4 π D t} e^{- 4 D t / L^{2}}$
3 $\frac{N}{16 π D t ^{3}} e^{- L^{2} / (4 D t)}$
4 $N e^{- 4 D t / L^{2}}$

Correct answer: —

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About this question

This Random Walk/Brownian motion/Diffusion PYQ is part of the Statistical Mechanics section of CSIR Net. Browse more Random Walk/Brownian motion/Diffusion questions or join the PhysicsByAaryan live batch for full conceptual coverage.