posted by Tommy on .
Hey can someone help me out? I only have 1 attempt left on this question and do not understand it at all!!!
A 3.5 kg balloon is filled with helium ( density = 0.179 kg/m^3).
If the balloon is a sphere with a radius of 5.2m , what is the maximum weight it can lift?
What is the weight of the air it displaces (volumeair*density*g) minus the weight of the balloon (mg)?
So volume of balloon 4/3*pi*r^3 *density of helium * g - ( 3.5 *9.81) ?
The answer of 999.9 N was one I already tried, and it was not correct :(
oops. I should have given you more.
The density in the first part is the density of air.
then the weight of the balloon has to include the weight of the helium (which is apparently not in the 3.5kg)
now is should work.