A cubic vessel (with faces horizontal + vertical) contains an ideal gas at NTP. The vessel is being carried by a rocket which is moving at a speed of 500 m s–1 in vertical direction. The pressure of the gas inside the vessel as observed by us on the ground
1
remains the same because 500m s−1 is very much smaller than vrms of the gas.
2
remains the same because motion of the vessel as a whole does not affect the relative motion of the gas molecules and the walls.
3
will increase by a factor equal to (v2rms + (500)2) / v2rms where vrms was the original mean square velocity of the gas.
4
will be different on the top wall and bottom wall of the vessel.