# Problem P. 3919. (October 2006)

**P. 3919.** There is a vertical cylinder filled with a sample of ideal gas in a thermostat. A horizontal piston which can move easily, splits the cylinder into two parts. The volume of the upper part is 4 times as much as the volume of the part below. If the cylinder is placed to a thermostat at a temperature of 400 K the ratio of the volumes of the upper and lower parts will be 3:1. Find the ratio of the number of molecules of the gas in the two parts of the cylinder.

(4 pont)

**Deadline expired on November 13, 2006.**

### Statistics:

111 students sent a solution. 4 points: 67 students. 3 points: 16 students. 2 points: 4 students. 1 point: 4 students. 0 point: 10 students. Unfair, not evaluated: 10 solutions.

Problems in Physics of KöMaL, October 2006