Question

give reason density of air decreases with increase in altitude​

Answer 1

$\bold{Hey \ Dude}$

which means that if both pressure and temperature decreases there will be an increase in volume since the fall of pressure will be much more rapid than the fall of temperature with altitude. Since the volume increases with altitude and the mass remains unchanged, the density also decreases with altitude.

Answer 2

which means that if both pressure and temperature decreases there will be an increase in volume since the fall of pressure will be much more rapid than the fall of temperature with altitude. Since the volume increases with altitude and the mass remains unchanged, the density also decreases with altitude.