18 m (Another review problem) A helicopter of mass 10,000 kg hovers at sea level while carrying a load of 14,000 kg. The blades cause an 18-m-diameter air mass to move downward at an average velocity proportional to the overhead blade rotational velocity (i.e., V = ka, where k is 0.036 (m/s)/rpm). Determine 1. the wof the helicopter blades in rpm 2. the required power output Calculate this on a day where the atmospheric pressure is 102 kPa and the temperature is 25 °C. Assume air approaches the blades from the top through a large area with negligible velocity and air is forced by the blades to move down with a uniform velocity through an imaginary cylinder whose base is the blade span area. Load 14,000 kg

18 m (Another review problem) A helicopter of mass 10,000 kg hovers at sea level while carrying a load of 14,000 kg. The blades cause an 18-m-diameter air mass to move downward at an average velocity proportional to the overhead blade rotational velocity (i.e., V = ka, where k is 0.036 (m/s)/rpm). Determine 1. the wof the helicopter blades in rpm 2. the required power output Calculate this on a day where the atmospheric pressure is 102 kPa and the temperature is 25 °C. Assume air approaches the blades from the top through a large area with negligible velocity and air is forced by the blades to move down with a uniform velocity through an imaginary cylinder whose base is the blade span area. Load 14,000 kg

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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