Balloon hanging slogan

Solution: Solution: According to the stress analysis of the balloon, as shown in the figure:

f float =ρGV = 1.29kg/m3× 10N/kg×9 m3 = 1 16. 1N；

g = Mg = 10k g× 10N/kg = 100N；

According to the force balance, F- tension =F buoyancy-g =116.1n-100n =16.1n;

So choose B.