JEE Mains · Physics · STD 11 - 12 . kinetic theory of gases
The number of air molecules per \(\mathrm{cm}^3\) increased from \(3 \times 10^{19}\) to \(12 \times 10^{19}\). The ratio of collision frequency of air molecules before and after the increase in number respectively is \(.........\)
- A \(1.25\)
- B \(0.25\)
- C \(0.75\)
- D \(0.50\)
Answer & Solution
Correct Answer
(B) \(0.25\)
Step-by-step Solution
Detailed explanation
Collision frequency, \(\mathrm{f}=\frac{\mathrm{V}}{\lambda}=\frac{\mathrm{V}}{\left(\frac{1}{\sqrt{2} \pi \mathrm{d}^2 \mathrm{n}_\psi}\right)}=\sqrt{2} \pi \mathrm{d}^2 \mathrm{vn}_v\) \(\therefore \mathrm{f} \propto \mathrm{n}_{\mathrm{v}}, \mathrm{n}_{\mathrm{v}}\) is number…
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