Chapter 7, Problem 72P

6.76 A wind turbine is operating in a 12 m/s wind that has a den- sity of 1.2 kg/m³. The diameter of the turbine silhouette is 4 m. The constant-pressure (atmospheric) streamline has a diameter of 3 m upstream of the windmill and 4.5 m downstream. Assume that the velocity distributions are uniform and the air is incom- pressible. Determine the force on the wind turbine. m P = Patm 4 Vz 4m 4 m Fx. Problem 6.76

For the position shown in the figure the spring is unstretched. The spring constant k, is designed such that after the system is released from rest, the speed of the mass is zero just as the 0.6 slug mass touches the floor. Find the spring constant, k and the maximum speed of block A and the location (distance above floor) where this occurs.

||! Sign in MMB241 - Tutorial L9.pd X PDF MMB241 - Tutorial L10.pX DE MMB241 - Tutorial L11.p x PDF Lecture W12 - Work and X File C:/Users/KHULEKANI/Desktop/mmb241/MMB241%20-%20Tutorial%20L11.pdf PDE Lecture W11 - Power and X Draw Alla | Ask Copilot ++ 3 of 3 | D 6. If the 50-kg load A is hoisted by motor M so that the load has a constant velocity of 1.5 m/s, determine the power input to the motor, which operates at an efficiency € = 0.8. 1.5 m/s 2 7. The sports car has a mass of 2.3 Mg, and while it is traveling at 28 m/s the driver causes it to accelerate at 5m/s². If the drag resistance on the car due to the wind is FD= 0.3v²N, where v is the velocity in m/s, determine the power supplied to the engine at this instant. The engine has a running efficiency of P = 0.68. 8. If the jet on the dragster supplies a constant thrust of T-20 kN, determine the power generated by the jet as a function of time. Neglect drag and rolling resistance, and the loss of fuel. The dragster has a mass of 1…