The volume of a balloon is 2000 m3. It is filled with helium of density 0.18 kg m–3. What load can it lift? Density of air is 1.29 kg m–3.
Answers
The volume of the He gas is, V = 100 m3
When a body of density ρ, volume V is immersed completely in a fluid of density σ then,
σ = 1.29 kg/m3 and ρ = 0.18 kg/m3
The observed weight of the body = W - w = Vρg - Vσg
according to question: W<w (ρ<σ)
Net force = W - w = Vρg - Vσg = Vg(0.18 - 1.29) = - 1087.8 N
Net force in the upward direction = 1087.8 N
It can lift a load having weight less then 1087.8 N
The balloon can lift a load less then 1087.8 N
Explanation:
Volume of the balloon = 2000 m³.
Density of helium = 0.18 kg m⁻³
Density of air = 1.29 kg m⁻³
Volume of helium = volume of balloon = 2000 m3
Given density of the balloon is ρ, and volume is V. It is immersed completely in a fluid of density σ. We know that
σ = 1.29 kg/m3 and ρ = 0.18 kg/m3.
The observed weight of the body = W - w = Vρg - Vσg
Given in question that W<w (ρ<σ)
Net force = W - w = Vρg - Vσg = Vg(0.18 - 1.29) = - 1087.8 N
Net force in the upward direction = 1087.8 N
So, the balloon can lift a load less then 1087.8 N