Gas impingement flux, problem in substituting constants

jjshan
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Homework Statement


gas impingement flux density is given by ∅=P/\sqrt{}2mkT
where m- mass of a molecule

show that
∅=3.513*1022P/\sqrt{}MT
where pressure in torr and M-molar mass of molecule
then ∅ in molecules per cm2 per second

Homework Equations




∅=3.513*1022P/\sqrt{}MT
where pressure in torr and M-molar mass of molecule
then ∅ in molecules per cm2 per second

The Attempt at a Solution



i substitute 1/133 to change pressure scale to torr and multiply by square root of Avogadro no and divide it by square root of 2∏k but i couldn't get appropriate constant. how derive the equation in given scale?
 
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jjshan said:
Homework Statement
gas impingement flux density is given by ∅=P/\sqrt{}2mkT
where m- mass of a molecule

It looks like you left out a factor of ##\pi## in the square root of the equation.

Consider:

What are the units of ∅ in the SI system?

What are the units of m in SI system?

What are the units of M?
 
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