The rms speed of oxygen molecule in a vessel at particular temperature is $\left(1+\frac{5}{x}\right)^{\frac{1}{2}} v$, where $v$ is the average speed of the molecule. The value of $x$ will be:
$\left(\right.$ Take $\left.\pi=\frac{22}{7}\right)$
Solution
<p>The relationship between the root-mean-square (rms) speed ($v_{rms}$) and the average speed ($v_{avg}$) of molecules in a gas can be found using the Maxwell-Boltzmann distribution. The rms speed and average speed are related as follows:</p>
$v_{rms} = \sqrt{\frac{3RT}{M}}$
$v_{avg} = \sqrt{\frac{8RT}{\pi M}}$
<p>Where:</p>
<ul>
<li>$R$ is the ideal gas constant</li>
<li>$T$ is the temperature in Kelvin</li>
<li>$M$ is the molar mass of the gas</li>
<li>$\pi$ is the mathematical constant pi</li>
</ul>
<p>In this problem, the rms speed of the oxygen molecule is given by:</p>
$v_{rms} = \left(1+\frac{5}{x}\right)^{\frac{1}{2}} v_{avg}$
<p>Now, let's divide the expression for $v_{rms}$ by the expression for $v_{avg}$:</p>
$$\frac{v_{rms}}{v_{avg}} = \frac{\sqrt{\frac{3RT}{M}}}{\sqrt{\frac{8RT}{\pi M}}} = \left(1+\frac{5}{x}\right)^{\frac{1}{2}}$$
<p>By simplifying the expression, we get:</p>
$$\frac{v_{rms}}{v_{avg}} = \frac{\sqrt{3}}{\sqrt{\frac{8}{\pi}}} = \left(1+\frac{5}{x}\right)^{\frac{1}{2}}$$
<p>Square both sides of the equation:</p>
$\frac{3}{\frac{8}{\pi}} = 1 + \frac{5}{x}$
<p>Now we will substitute the provided value of $\pi = \frac{22}{7}$:</p>
$\frac{3}{\frac{8}{\frac{22}{7}}} = 1 + \frac{5}{x}$
<p>By simplifying the expression, we get:</p>
$\frac{3 \cdot \frac{22}{7}}{8} = 1 + \frac{5}{x}$
<p>Now let's solve for $x$:</p>
$\frac{66}{56} - 1 = \frac{5}{x}$
$\frac{10}{56} = \frac{5}{x}$
<p>Multiplying both sides by $x$:</p>
$\frac{10}{56}x = 5$
<p>Finally, solving for $x$:</p>
$x = \frac{5 \cdot 56}{10} = 28$
<p>So, the value of $x$ is $\boxed{28}$.
About this question
Subject: Physics · Chapter: Thermodynamics · Topic: Zeroth and First Law
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