Question

Four particles have speed $2,3,4$ and $5$ cm/s respectively. Their rms speed is

• A. 3.5 cm/s
• B. (27/2) cm/s
• C. $\sqrt{54}cm/s$
• D. $\sqrt{54}/2cm/s$

Answer 1

Answer: (D)

$u_{\text{ms }}=\sqrt{\left[\frac{2^2+3^2+4^2+5^2}{4}\right]}$

$=\sqrt{\left[\frac{54}{4}\right]}cm{s}^{-1}$