Medal
The volume of this balloon should be 1.11 m3. Typically air density is 1190 g/m3. Calculate the mass of unheated air displaced by the balloon when it hovers. Show your work.

Question

Medal
  The volume of this balloon should be 1.11 m3.  Typically air density is 1190 g/m3.  Calculate the mass of unheated air displaced by the balloon when it hovers.  Show your work.

irishboy123 · Answer

as it stands, the balloon will have a density that is the same as the surrounding air.  its mass will be this density times its given volume.  

it is confusing that the question implies that its air has been heated.  if that was true, it should be less dense than the "unheated air".  it should not hover, it should rise.

you would need to have a force driven by, say the mass of the balloon material or a weight suspended from the balloon, acting downwards in order for the balloon to require an upwards acting bouyant (Archimedes) force due to its lesser density.

that bouyant force would be the volume times the difference in densities.