Question

A balloon filled with a lighter gas occupies a volume of 1500 cu metre. Its mass (mass of material of balloon + mass of gas in it) is 1650 kg. Its tied with a rope and floating in air of density 1.3 kg/cubic metre. The pull on the rope is ?

Answer 1

The pull on the rope is `=2940N`

Explanation:

The Buoyancy force is

`F_b=V*rho*g`

The volume of the balloon is `=1500m^3`

The density of air is

`rho=1.3kgm^-3`

The acceleration due to gravity is `g=9.8ms^-2`

The mass of the ballloon is `m=1650kg`

The weight of the balloon is `w=1650*9.8=16170N`

The buoyancy force is

`F_b=1500*1.3*9.8=19110N`

The pull on the rope is

`F_b-w=19110-16170=2940N`