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NEET PHYSICSKinetic TheoryEasy

Question

The mean free path l for a gas molecule depends upon the diameter, d of the molecule as:

A

l \propto 1/d²

B

l \propto d

C

l \propto d²

D

l \propto 1/d

Step-by-Step Solution

According to the kinetic theory of gases, the mean free path (ll) is defined as the average distance a molecule travels between successive collisions. It is mathematically expressed as l=12πnd2l = \frac{1}{\sqrt{2} \pi n d^2}, where nn is the number density of the gas and dd is the diameter of the molecule. From this expression, it is evident that the mean free path is inversely proportional to the square of the diameter of the molecule (l1d2l \propto \frac{1}{d^2}).

Exam Context & Concepts Covered

This question aligns with the NEET PHYSICS syllabus, specifically targeting concepts from Kinetic Theory. Mastering this topic is crucial for scoring well in the upcoming medical entrance examinations. Solving conceptually related problems will help you understand the nuances of these concepts and improve your problem-solving speed.

PHYSICSKinetic Theorymoleculedependsdiametermolecule

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