Aptitude Test Problems in Physics Science for Everyone by S Krotov ( PDFDrive.com )

56 Aptitude Test Problems in Physics

2.7. A vessel of volume V = 30 1 is sepa-

rated into three equal parts by stationary

semipermeable thin particles (Fig. 61). The

H2 02 N 2

Fig. 61

left, middle, and right parts are filled with

mH, = 30 g of hydrogen, mo, = 160 g of

oxygen, and mN, = 70 g of nitrogen respec-

tively. The left partition lets through only

hydrogen, while the right partition lets

through hydrogen and nitrogen.

What will be the pressure in each part of

the vessel after the equilibrium has been

set in if the vessel is kept at a constant

temperature T = 300 K?

2.8*. The descent module of a spacecraft

approaches the surface of a planet along the

vertical at a constant velocity, transmit-

ting the data on outer pressure to the

spacecraft. The time dependence of pressure

(in arbitrary units) is shown in Fig. 62.

The data transmitted by the module after

landing are: the temperature T = 700 K

and the free-fall acceleration g = 10 mis 2.

Determine (a) the velocity v of landing of

the module if the atmosphere of the planet

is known to consist of carbon dioxide CO 2 ,

and (b) the temperature Th at an altitude

h = 15 km above the surface of the planet.