CAPE Physics Unit 1 · 2015 · Paper 1 · Question Q43

Helium gas is kept in a container at a pressure of 1.7 \times 10^5\text{ Pa}. If the density of helium is 0.92\text{ kg m}^{-3}, then what is the root mean square speed of the helium atoms?

1. (A)248\text{ m s}^{-1}
2. (B)330\text{ m s}^{-1}
3. (C)430\text{ m s}^{-1}
4. (D)745\text{ m s}^{-1}