A wind turbine having an efficiency of 35% and rotor diameter of 33 m is exposed to air flowing at a speed of 6 m/s. Find the power developed by the turbine. Assume ρ = 1.2 kg/m3. [Ans.: 38.8 kW].

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Hi please show calculations or diagrams if required thank you

Answer: 57.4 ft/s=17.5m/sTorricelli's equation does not apply but the simplified Bernoulli's equation does apply.

2. Some of the first power-generating wind turbines were small, having blades with a radius of 8.00 meters. Currently, the largest wind turbine has a radius of 164 meters. Because the small wind turbines are closer to the ground, they often experience smaller wind speeds. Given the information below, how many small wind turbines would be needed to produce the same power output as one large wind turbine? For both wind turbines, assume the air density is 1.23 kg m³. Small Wind Turbine Large Wind Turbine Wind turbine blade radius 8.00 m 164 m Wind turbine efficiency 35% 45% Wind speed 3.50 m s1 5.50 m s1

1.1. The pump whose performance curves are shown in Figure P1.1 is operated at 1750 rpm and is connected to a 2-in. i.d. galvanized iron pipe 175 ft long. What will be the flow rate and power input? 100 90 Head curve 80 70 60 50 40 -Efficiency 30 20 10 20 40 60 80 100 120 140 160 180 Flow rate (gpm) FIGURE P1.1 Performance curves for a pump with a 9-in. impeller and speed 1750 rpm. 1.7. If the pump and pipe arrangement of Problem 1.1 now includes an elevation increase of 30 ft, what flow will result? Head rise (ft); efficiency ()

Nhand,A 75 N ma = 3 kg %D VA = 8 m/s Block Block Block Block B A Hx = 0.4 %3D 2 m Ax Note: Diagram is not drawn to scale A hand pushes block A (m,= 3 kg) with a constant force Nand. A= 75 N for a distance Ax 2 m along a (mostly) frictionless table such that it speeds up from rest and is traveling at a speed of 8 m/s after it slides over a rough section of the table (H = 0.4). Block A then collides with a more massive block B (mg = 6 kg) that is initially at rest. Find the speed of block A after it has been released by the hand and just before the rough section of the table. A) 10 m/s B) 20 m/s C) 30 m/s D) 40 m/s E) 50 m/s O A O B O D O E

Imagine the water level in the tank as shown in the Figure rises at a rate of 0.004579 ft³/sec. then find: i) The volume flowrate of water leaving the tank (Q3) in ft³/s from pipe 3. ii) The average velocity of water leaving the tank (V3) in ft/s from pipe 3. Pipe 1: Qi=0.0109 ft²/s Pipe 2: Q₂ = 0.025 ft³/s Pipe 3: dy = 1.5 in. V₁ = ?! Q₁ =?

EX.1 An axial flow pump with an impeller rotor diameter of 30 cm handles water at a rate of 2.7 m*/minute running at 1500 rpm. The energy input is K o W 125 J/kg and Total to Total efficiency is 0.75. If a geometrically similar pump has a diameter of 20 cm running at 3000 rpm, find its: i) Flow rate ii) input power.