Question

Find the kinetic energy per unit volume of nitrogen at a pressure of 76 cm of mercury. Hence, find the kinetic energy of 10 cm³ of the gas under the same condition. Take ρ (mercury) = 13.6 g/cm³ and g = 9.8 m/s² .

Answer 1

Data : h = 76 cm = 0.76 m, ρ = 13.6 g/cm³ 

= 13.6 × 10³ kg/m³ , g = 9.8 m/s²,

V = 10 cm³ = 10 × 10^-6 cm³

(i) The kinetic energy per unit volume of nitrogen

(ii) The kinetic energy of 10 cm³ of the gas =

PV= (1.519 × 10⁵) (10 × 10^-6)

= 1.519 J