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NEET PHYSICSKinetic TheoryMedium

Question

If the mean free path of atoms is doubled then the pressure of the gas will become:

A

P/4

B

P/2

C

P/8

D

P

Step-by-Step Solution

The mean free path (λ\lambda) of a gas molecule is inversely proportional to the number density (nn) of the gas molecules, given by the formula λ=12πnd2\lambda = \frac{1}{\sqrt{2}\pi n d^2}. The pressure (PP) of an ideal gas is directly proportional to the number density at a constant temperature (P=nkTP = nkT). Combining these relationships, the mean free path is inversely proportional to the pressure (λ1P\lambda \propto \frac{1}{P}). Therefore, if the mean free path is doubled, the pressure must be halved to maintain the relationship.

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 Theorydoubledpressurebecome

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B.l ∝ d
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