The weight of an empty balloon on a spring balance is $w_1$. The weight becomes $w_2$ when the balloon is filled with air. Let the weight of the air itself be $w$ .Neglect the thickness of the balloon when it is filled with air. Also neglect the difference in the densities of air inside $\&$ outside the balloon. Then :
A$w_2 = w_1$
B$w_2 = w_1 + w$
C$w_2 < w_1 + w$
D$A$ and $C$ both
Diffcult
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