Question

$ KE $ per unit volume is $ E $ . The pressure exerted by the gas is given by

• A. $ \frac{E}{3} $
• B. $ \frac{2E}{3} $
• C. $ \frac{3E}{2} $
• D. $ \frac{E}{2} $

Answer 1

Answer: (B)

The pressure exerted by the gas,
$p = \frac{1}{3} \, p \overline{c^2} $
$= \frac{ 1 m}{ 3 \, V} \overline{c^2}$
$= \frac{2}{3} \bigg( \frac{1}{2} m \overline{c^2} \bigg) $
$ ( \therefore \frac{1}{2} m \overline{c^2} = \frac{E}{V} = $ energy per unit volume, V = 1)
p= $ \frac{2}{3} $ E