There is a very small hole in a totally enclosed heated furnace. Outside the furnace, the air temperature is  $0^{0}C$ and the air pressure is 100 kPa. The air inside the furnace is kept at a constant temperature of  ${57}^{0}C$ by the controlled heating system, and after a sufficiently long time its pressure also becomes stationary. Calculate (to the nearest integer) the magnitude of this stationary pressure.

The number of molecules passing through a hole of cross–sectional area A during a time interval t is Av Nt, where v is the component, perpendicular to the wall, of the average molecular velocity, and N is the number density (the number of particles in unit volume). At equilibrium no. of molecules going out should be equal to the number of molecules going in.
The square of the speed of the molecules (a measure of the internal energy of the gas) is proportional to the gas temperature T, and, from the ideal gas equation, the number density is proportional to the quotient of the pressure p and the temperature.