Traveling to Fairy Lake in summer vacation, Xiao Fang personally experienced sailing. As shown in the figure, the sailboat ...

When he boarded the sailboat,

△f float =g=mg=50kg× 10n/kg=500n,

∫△f float = ρ water△ V row G,

Volume added value of boiling water:

△v line =

△f floating

ρ water g

=

500 newtons

/kloc-0 /×103kg/m3×10 cattle/kg

= 0.05m3

(2)∫p =

f

s

∴ Maximum thrust of the wind on the sail:

f = ps = 40pa× 6m2 = 240n

(3) The work done by the wind to the sailboat in time t:

W useful =fs=fvt=280n×6m/s×t,

Energy gained by sailboat in time t:

W total =8× 102j/(m2？ s)×6m2×t，

Wind energy utilization rate of sailboats;

η=

W is useful

Manager w

=

280 Newton× 6m/s× ton

8× 102j/(m2？ s)×6m2×t，

=35%.

Answer: (1) When he boarded a 50kg sailboat, the volume of boiling water discharged by the sailboat increased by 0.05m3；;

(2) According to relevant data, when the wind speed on the lake is 8m/s, the wind pressure is 40pa, and the maximum thrust of the wind on the sail is 240n；;

(3) The wind energy utilization rate of sailboats is 35%.