Question

A spherical hot air balloon of diameter 30.0 meters just floats (hovers) when the hot air inside has been heated to a density of 1.10 kg/m3 What is the weight of the balloon and cargo (not including the air inside) if the surrounding air has a density of 1.20 kg/m3? (VSphere = (4/3)nr3)

Answer 1

Answer:

W = 166422.729 N

Explanation:

given,

diameter of the balloon = 30 m

density of the air = 1.10 Kg/m³

weight of the balloon and cargo = ?

density of the surrounding air = 1.20 kg/m³

we know,

Density = mass/volume

m = density x volume

$m = \rho\times \dfrac{4}{3}\pi r^3$

$m =1.20 \times \dfrac{4}{3}\pi\times 15^3$

m = 16964.6 Kg

Weight of the balloon

 W = m g

 W = 16964.6 x 9.81

W = 166422.729 N

Weight of the balloon and the cargo is equal to  W = 166422.729 N