a. For a given location, the wind speed at 10m and 50m heights above ground has been measured to be 4 m/s and 6.8 m/s respectively. Find the wind speed at 90m height. b. A wind turbine has a 3MW rated power output at standard air density (15°C, 1 atm). Estimate the change of rated power if the turbine operates at a temperature of 30°C. c. For the 3MW turbine (from part b), estimate the change of the rated power relative to the sea level conditions, if the turbine is installed at 2000 m altitude above the sea.

a. For a given location, the wind speed at 10m and 50m heights above ground has been measured to be 4 m/s and 6.8 m/s respectively. Find the wind speed at 90m height. b. A wind turbine has a 3MW rated power output at standard air density (15°C, 1 atm). Estimate the change of rated power if the turbine operates at a temperature of 30°C. c. For the 3MW turbine (from part b), estimate the change of the rated power relative to the sea level conditions, if the turbine is installed at 2000 m altitude above the sea.

University Physics Volume 1

18th Edition

ISBN:9781938168277

Author:William Moebs, Samuel J. Ling, Jeff Sanny

Publisher:William Moebs, Samuel J. Ling, Jeff Sanny

Chapter7: Work And Kinetic Energy

Section: Chapter Questions

Problem 25P: (a) Calculate the work done on a 1500-kg elevator car by its cable to lift it 40.0 m at constant...

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