Question

A balloon of volume 100 ${ms}^{-1}$ is filled with hot air of density 0.40 kg ${ms}^{-1}$. If the fabric of balloon weighs 16 kgf and equipment P is attached to it , such that balloon is in the state of equilibrium.
Calculate weight of combined hot air and balloon ?

• A. 46kgf
• B. 40kgf
• C. 56kgf
• D. 50kgf

Answer 1

The correct option is C 56kgf

Fabric of balloon weight $=16Kgf$

$=16\times 10N$

$=160N$

If the fabric of balloon weight $=16kgf$

Explanation :-

Total mass of water -

$M=V\times d$

$M=100\times 0.4$

$M=40$ Kg

Mass of balloon fabric :-

$M=16kg$

Total weight of equipment $=$

$W=(m+M)g$

$W=(40+16)\times 10$

$=560N$

$=56Kgf$