Mechanical Engineering Questions and Answers March 25, 2020

The power coefficient of a 5.25 kW micro wind turbine is 48.5% and the gearbox/generator efficiency is 87.8% efficient. The air density is 1.225 kg/m3. The rated wind speed is 10.0 m/s. a) What is the swept area of the wind turbine rotor? b) What is the diameter of the wind turbine rotor? c) What is the effectiveness of the wind turbine (%)?

The Pelton wheel of a hydroelectric power plant has the following specifications: The average radius of the wheel is 1.70 m; the exit diameter of the nozzle is 9.97 cm; the jet velocity is 90 m/s; and the turning angle of the buckets is 165. Determine the volume flow rate through the turbine and the rotational speed of the wheel (in rpm) for

The blocks A and B shown are initially at rest and have masses of mA=225 kg and mB=105 kg . Neglect the mass of the rope and pulley system and assume block B moves only in the vertical direction, parallel to the y-axis. Neglect the effects of friction. Part A - Acceleration of Block B If the blocks are released from rest, determine the magnitude

A B

Suppose that a 44 kg cylinder that spins at 36 rad/s clockwise about its axis is dropped (gently) onto a horizontal surface. Assume that the coefficient of kinetic friction is k = 0 Find the speed, v, of the center of mass G when pure rolling motion begins. Through what distance has G moved on the surface before pure rolling begins? Radius of