Kinetic Theory - Result Question 14

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14. In a vessel, the gas is at a pressure $P$. If the mass of all the molecules is halved and their speed is doubled, then the resultant pressure will be

======= ####14. In a vessel, the gas is at a pressure $P$. If the mass of all the molecules is halved and their speed is doubled, then the resultant pressure will be

3e0f7ab6f6a50373c3f2dbda6ca2533482a77bed:content/english/neet-pyq-chapterwise/physics/kinetic-theory/kinetic-theory—result-question-14.md (a) $4 P$

(b) $2 P$

(c) $P$

(d) $P / 2$

[NEET Kar: 2013]

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Answer:

Correct Answer: 14. (b)

Solution:

  1. (b) $\because P=\frac{1}{3} \frac{m N}{V} v_rms^{2}$

where $m=$ mass of each molecules

$N=$ total number of molecules

$V=$ volume of the gas

When mass is halved and speed is doubled then

Resultant pressure, $P^{\prime}=\frac{1}{3} \times(\frac{m}{2}) \times \frac{N}{V}(2 v _{rms})^{2}$

$ =2 P $