Answer:
F = 12,387 Newtons
Steps to complete the problem:
 List all of the variables given.
Mass of balloon = 80 kg
Volume of balloon = 1200 m^{3}
Density of Helium = .18 kg/m^{3}
Density of Air = 1.3 kg/m^{3}
 Determine the the total mass that can be lifted by
the helium balloon.
Mass lifted = mass of the volume of fluid
displaced
Mass = (1200 m^{3})( 1.3 kg/m^{3})
Mass = 1560 kg
The total amount that can be lifted = 1560 kg
(including balloon, helium and payload)


 Determine the mass that is displaced.
 Determine the mass of helium.
(1200 m^{3})*(.18
kg/m^{3}) = 216 kg
 Subtract the mass of the balloon and mass
of the 1200 m^{3} volume of helium from the
total mass that can be lifted.
1560 kg  80 kg  216 kg = 1264 kg
 Determine the Force required to lift the displace
volume of 1200 m^{3}.
F = mg (where g is gravity)
F = (1264 kg) * (9.8 m/s^{2})
F = 12,387 Newtons


Return to Bouyancy
Lesson

