The number of watts which is the power of the turbine for each case is respectively; 600 W; 506.25 W; 300 W
We are given;
Density of air; ρ = 1.2 kg/m³
Area; A = r² with r being the blade length
Formula for power in turbine is;
P = ¹/₂ρAv³
1) v = 10 m/s and r = 1 m.
Thus;
P = ¹/₂ * 1.2 * 1² * 10³
P = 600 W
2) v = 15 m/s and r = 0.5 m.
Thus;
Power = ¹/₂ * 1.2 * 0.5² * 15³
P = 506.25 W
3) v = 20 m/s and r = 0.25 m.
Thus;
Power = ¹/₂ * 1.2 * 0.25² * 20³
P = 300 W
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