Physics check my answer please
posted by Maya .
The atmosphere on Mars is almost all carbon dioxide (CO2), and has a pressure of about 6.9×102 Pa, much less than that of Earth. At −22°C (a warm day on Mars), what is the mass of one cubic meter of the atmosphere? (Assume the atmosphere is completely CO2.)
I got 0.020 using the equation (1/2) m v^2 = (3/2) K T.
Am I right? If not, what do I need to do and what answer should I get?