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.l Neglect the thickness of the balloon when it is filled with air. Also neglect the difference in the density of air insider and outside the balloonn

Options

A. `W_(2)=W_(1)+W`
B. `W_(2)=sqrt(W_(1)W)`
C. `W_(2)=W_(1)`
D. `W_(2)=W_(1)-W`

Answer

C

Explanation

Apparent weight of the balloon `= W_(2)`
Apparent weigt `=` real weight `-` upthrust
or `W_(2)=` real weight `=W_(1)+W`
`:. W_(2)=W_(1)+W-W=W_(1)`