Slogan of poverty alleviation honey pomelo

Solution: As shown in the figure, the resultant force of the buoyancy of the balloon, the gravity of the slogan and the string, and the tension of the rope should be a pair of balancing forces.

F float = ρ GV =1.29kg/m3×10n/kg× 6m3 = 77.4N.

G=mg=5kg× 10N/kg=45N

According to the force balance, F- tension = F- buoyancy-g = 77.4 n-45 n = 32.4 n.

So the answer is: 32.4.