Approximate the theoretical power in wind moving at a speed of 6 m/s with an air temperature of 40°F striking wind turbine with a 5 ft diameter rotor (use mass density = 1.277 kg/m3). a.2,707.97 W b.75.22 W c.251.57 W d.None of these e.6.99 W

explanation of the performance tests undertaken for a wind turbine. With the options found, give a justified recommendation for the best system.

OO O0I 94) 8:50 EXAMPLE Given: A sports car has a mass of 2 Mg and an engine efficiency of ɛ = 0.65. Moving forward, the wind creates a drag resistance on the car of F, = 1.2v2 N, where v is the velocity in m/s. The car accelerates at 5 m/s?, starting from rest. Find: The engine's input power when t = 4 s. Plan: 1) Draw a free body diagram of the car. 2) Apply the equation of motion and kinematic equations to find the car's velocity at t = 4 s. 3) Determine the power required for this motion. 4) Use the engine's efficiency to determine input power. nashat N •..

A wind generator rotates at 17 rpm on the rotor (the part with the blades). It is a direct drive (meaning the rotor connects directly to the generator). The generator is 86% efficient and produces 3.1 MW. What is the torque on the rotor?

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Question B3 The engine of an aeroplane is equipped with an ideal convergent nozzle with an area ratio Ainlet 2.035 ( -A-2.035), as in Figure Q-B3. The aeroplane is flying at an altitude of 11 Aexit km where the atmospheric pressure and temperature are 0.23 bar and 216K respectively. You may assume the combustion gases entering the nozzle have the same property as air (i.e. y=1.40, R=287 J/kgK and Cp-1004.5J/kgK). Page 6 Question B3 continued inlet exit Amles/Aexit -AVAJ-2.035 Figure Q-B3 a) If the nozzle operates at its critical condition, calculate: the inlet Mach number M;. nozzle's exit velocity V, the inlet stagnation pressure Por- the inlet static pressure FG The stagnation Aj P, and the nozzle's gross thrust per unit exit area temperature of the gases entering the nozzle is To 1200 K. b) If the stagnation pressure at the inlet of the nozzle is reduced to 80% of its value in part (a), determine the exit static temperature 7;, the nozzle's gross thrust per unit exit area FG. The…