States of Matter - Result Question 17

17. For a monatomic gas kinetic energy $=E$. The relation with rms velocity is

(a) $u=\left(\dfrac{2 E}{m}\right)^{1 / 2}$

(b) $u=\left(\dfrac{3 E}{2 m}\right)^{1 / 2}$

(c) $u=\left(\dfrac{E}{2 m}\right)^{1 / 2}$

(d) $u=\left(\dfrac{E}{3 m}\right)^{1 / 2}$

(2004, 1M)

Show Answer

Answer:

Correct Answer: 17. (a)

Solution:

Kinetic energy $(E)=\dfrac{3}{2} k T$

$ \begin{aligned} \text { RMS speed }(u) & =\sqrt{\dfrac{3 k T}{m}} \\ \Rightarrow \quad u & =\sqrt{\dfrac{2 E}{m}} \end{aligned} $